ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Journals
  • Articles  (1,042)
  • Electron microscopy  (1,042)
  • Springer  (1,042)
  • Medicine  (1,042)
  • Economics
  • Architecture, Civil Engineering, Surveying
  • 1
    Electronic Resource
    Electronic Resource
    Biocompatibility of MPC: in vivo evaluation for clinical application (2000)
    Springer
    Journal of artificial organs 3 (2000), S. 39-46 
    Details
    ISSN: 1619-0904
    Keywords: Poly(2-methacryloyloxyethyl phosphorylcholine-co-n-butyl methacrylate) (MPC) ; In vivo biocompatibility ; Artificial endocrine pancreas ; Electron microscopy ; Glucose sensor
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Technology
    Notes: Abstract Biocompatibility is important to assure a mild body reaction to an implanted device and its long-term stability and functionality. In diabetes research, subcutaneously implanted glucose monitoring systems need biocompatible surfaces for long-term application. The biocompatibility of poly(2-methacryloyloxyethyl phosphorylcholine-co-n-butyl methacrylate) (MPC), a material similar to the phospholipid layer of a cell membrane, was compared in vivo with the biocompatibility of polyurethane (PU), polyvinyl alcohol (PVA), and cuprophane (CUP). Needle-type glucose sensors and hollow-fiber probes used for microdialysis were coated with these four different biomaterials and implanted subcutaneously in 18 rats and 7 healthy volunteers. At set intervals, the implants and, in the case of the rats, also the surrounding tissue were removed and characterized by light and electron microscopy. MPC-coated sensors and hollow-fiber probes showed smooth and thin deposits in flat layers, whereas the surface deposits on PU- and PVA-coated sensors and those on CUP hollow-fiber probes appeared as rough, irregular, and dense attachments of aggregated cells and protein. This study confirmed results from earlier in vitro tests by showing the biocompatibility and reliability of MPC. Even though the amount of protein and cells attached to the MPC surface was not as low as expected from in vitro experiments, the biocompatibility and long-term stability of the implanted devices were superior to those of PU, PVA, and CUP.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02479925
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Types, numbers and distribution of synapses on the dendritic tree of an identified visual interneuron in the brain of the locust (1999)
    Springer
    Cell & tissue research 296 (1999), S. 645-665 
    Details
    ISSN: 1432-0878
    Keywords: Key words Descending contralateral movement detector (DCMD) ; Identified neuron ; Vesicles ; Electron microscopy ; 3-D reconstruction ; Locust ; Schistocercagregaria (Insecta)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  The descending contralateral movement detector (DCMD), an identified descending interneuron in the brain of the locust Schistocerca gregaria has been investigated by using light and electron microscopy. We describe the fine structure, distribution and numbers of synapes that it receives from another identified brain neuron, the lobular giant movement detector (LGMD), and from unidentified neurons. The DCMD dendrites emerging from the integrative segment vary in form and number between individuals and sexes but always form a flattened dendritic domain. The arborizations and the integrative segment appear to be exclusively postsynaptic. Two types of synaptic contacts (Type 1 and 2) onto the DCMD can be discerned as having either round (Type 1) or pleiomorphic synaptic vesicles (Type 2) and by large (Type 1) or small (Type 2) subsynaptic appositions. Contact zones of Type 1 synapses are smaller than those of Type 2. LGMD-synapses are of Type 1 and occur intermingled with presynaptic sites of unidentified units. Some branches of the DCMD receiving input from unidentified units are devoid of contacting LGMD processes. Synapses of both types are randomly distributed over the DCMD integrative segment and at fibres with similar sizes.Type 1 synapses are much more frequent than Type 2 synapses and their number is negatively correlated with fibre diameter. For a whole DCMD dendritic arborization, a total of 8500 active zones of chemical synapses has been calculated, including a mininum of 2250 LGMD-synapses and about 1000 Type 2 synapses. The DCMD may thus receive a considerable amount of input from as yet unidentified neurons.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410051325
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Metaphase-specific cell death in meiotic spermatocytes in mice (1999)
    Springer
    Cell & tissue research 296 (1999), S. 359-369 
    Details
    ISSN: 1432-0878
    Keywords: Key words Apoptosis ; Electron microscopy ; Meiosis ; Spermatocytes ; Spermatogenesis ; Testis ; TUNEL ; Mouse (10 strains)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  Apoptosis of male germ cells is a widespread but little-understood phenomenon in many animal species. The elucidation of its mechanisms could be useful in the understanding of male infertility. We have examined the distribution of dying cells with the terminal transferase-mediated nick-end labeling (TUNEL) method and by an electron-microscopic procedure in the testes of 10 mouse strains, viz., C57BL/10 (B10), SL/NiA (SL), C57BL/6 (B6), C3H/He (C3H), BALB/c (BALB), DBA2 (DBA), CBA/J (CBA), MRL/MpJ-+/+ (M+), MRL/MpJ-lpr/lpr (lpr), and wild-type NJL mice (Mus musculus musculus). In the testes of the B10, NJL, SL, B6, C3H, BALB, DBA, and CBA mice, very few TUNEL-positive cells are distributed in the seminiferous tubules, whereas in the testes of the M+ and lpr mice, many TUNEL-positive cells, which are restricted to stage XII seminiferous tubules, have been identified. The most important finding is that many metaphases of meiotic spermatocytes show a marked TUNEL-positive reaction. Some metaphases show apoptotic morphology electron-microscopically. These results suggest that the testes of MRL strains will provide a useful model for the study of the mechanism of metaphase-specific apoptosis in meiotic spermatocytes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410051296
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Effect of high-level oxygen exposure on the peroxidase activity and the neuromelanin-like pigment content of the nerve net in the earthworm, Lumbricus terrestris (1999)
    Springer
    Cell & tissue research 295 (1999), S. 349-354 
    Details
    ISSN: 1432-0878
    Keywords: Key words Neuromelanin ; Neuron ; Peroxidase ; Oxygen metabolism ; High-definition light microscopy ; Electron microscopy ; Ultrastructure ; Cytochemistry ; Substantia nigra ; Lumbricusterrestris (Annelida)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Histochemical examination of 1-μm tissue sections from the dorsal nerve plexus of the earthworm, Lumbricus terrestris, reveals multiple brown intraneuronal granules. These granules contain material morphologically and histochemically consistent with neuromelanin. When viewed with transmission electron microscopy, these were seen as single membrane-enclosed biphasic granules with diameters of 370–730 nm. Exposure of L. terrestris to high-level environmental oxygen resulted in an increase in the number of neuromelanin-like pigment granules within the neurons of the circular muscle layer. As measured by ortho-phenylenediamine hydrochloride, the endogenous peroxidase activity of extracts from worms incubated in high-level environmental oxygen was 51% more than controls. The endogenous peroxidase activity was localized in situ with 3,3-diaminobenzidine (DAB) and was found to increase in and around the neuromelanin-like pigment-containing neurons within the circular muscle layer. These studies suggest that the nerve net of L. terrestris may serve as a model to study the role of neuromelanin production in oxidative stress and its relationship to endogenous peroxidases.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410051241
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Op/op mice defective in production of functional colony-stimulating factor-1 lack macrophages in muscularis externa of the small intestine (1999)
    Springer
    Cell & tissue research 295 (1999), S. 485-493 
    Details
    ISSN: 1432-0878
    Keywords: Key words Immunohistochemistry ; Electron microscopy ; Interstitial cells of Cajal ; F4/80 ; CSF-1 ; Kit-receptor ; Mouse (op/op)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The osteopetrotic (op/op) mutant mouse possesses an inactivating mutation in the colony-stimulating factor-1 (CSF-1) gene, which results in the absence of certain macrophages and in osteopetrosis, following a lack of osteoclasts. Studies of the op/op mouse indicate that CSF-1-dependent tissue macrophages may belong to a trophic and/or scavenger subpopulation, which through their effect on other cell types can significantly affect tissue functions, and that cells which are CSF-1 independent have antigen presentation and immunological functions.We have previously identified a cell system of regularly distributed macrophages in the muscularis externa of the small intestine and wanted to extend these studies to the op/op mouse.The present investigations with light- and electron-microscopic methods using fluorescent dextran, methylene blue and immunohistochemistry (F4/80, anti-kit receptor, anti-CD3, anti-CD45R/B220) show that macrophages are absent from the muscle layers, with only an occasional macrophage present in the subserosa. In the lamina propria and submucosa, macrophage numbers are reduced. In all other respects the muscularis externa appears normal, including normal organization and number of interstitial cells of Cajal. Control and op/op mice both lack cells expressing CD3 (T lymphocytes), CD45R/B220 (B lymphocytes) and mast cells in the muscularis externa. This leaves the muscularis externa macrophages as the most likely source of local cytokine production under such conditions as postoperative ileus and intussusception in infants, where the muscularis externa appears to be one target of cytokines. We conclude that the lack of macrophages, combined with the preservation of otherwise normal structure, will make the op/op mouse a valuable model by which to assess the functions and relative importance of the muscularis externa macrophages in relation to intestinal motility under normal and pathological conditions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410051254
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Caveolin and its cellular and subcellular immunolocalisation in lung alveolar epithelium: implications for alveolar epithelial type I cell function (1999)
    Springer
    Cell & tissue research 295 (1999), S. 111-120 
    Details
    ISSN: 1432-0878
    Keywords: Key words Caveolin ; Caveolae ; Lung ; Alveolar epithelial type I cell ; Immunocytochemistry ; Electron microscopy ; Confocal laser scanning microscopy ; Rat (CD)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Caveolae are flask-shaped invaginations of the plasmalemma which pinch off to form discrete vesicles within the cell cytoplasm. Biochemically, caveolae may be distinguished by the presence of a protein, caveolin, that is the principal component of filaments constituting their striated cytoplasmic coat. Squamous alveolar epithelial type I (ATI) cells, comprising approximately 95% of the surface area of lung alveolar epithelium, possess numerous plasmalemmal invaginations and cytoplasmic vesicles ultrastructurally indicative of caveolae. However, an ultrastructural appearance does not universally imply the biochemical presence of caveolin. This immunocytochemical study has utilised a novel application of confocal laser scanning and electron microscopy unequivocally to localise caveolin-1 to ATI cells. Further, cytoplasmic vesicles and flask-shaped membrane invaginations in the ATI cell were morphologically identified whose membranes were decorated with anti-caveolin-1 immunogold label. Coexistent with this, however, in both ATI and capillary endothelial cells could be seen membrane invaginations morphologically characteristic of caveolae, but which lacked associated caveolin immunogold label. This could reflect a true biochemical heterogeneity in populations of morphologically similar plasmalemmal invaginations or an antigen threshold requirement for labelling. The cuboidal alveolar epithelial type II cell (ATII) also displayed specific label for caveolin-1 but with no ultrastructural evidence for the formation of caveolae. The biochemical association of caveolin with ATI cell vesicles has broad implications for the assignment and further study of ATI cell function.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410051217
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Distribution and submicroscopic immunogold localization of cellular prion protein (PrPc) in extracerebral tissues (1998)
    Springer
    Cell & tissue research 292 (1998), S. 77-84 
    Details
    ISSN: 1432-0878
    Keywords: Key words Prion protein (PrPc) ; Electron microscopy ; Secretory granules ; Membrane ; Extracerebral tissues ; Hamster ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  In transmissible spongiform encephalopathies (TSE), such as scrapie in animals and Creutzfeldt-Jakob disease in humans, the central event is the conversion of a host-encoded amyloidogenic protein (PrPc) into an abnormal isoform (PrPsc) that accumulates as amyloid in TSE brain. PrPc is a membrane sialoglycoprotein synthesized in the central nervous system and elsewhere. We have examined the ultrastructural localization of PrPc in numerous hamster and some human extracerebral tissues, by means of a post-embedding electron-microscopic method combined with immunogold labeling. In stomach, intestine, lung, and kidney from hamsters, and in stomach, kidney, and spleen from humans, immunogold labeling specific for PrPc is observed on various cellular substructures related to secretory pathways: Golgi apparatus, secretory globules, and plasma membrane. In mucous epithelial cells of stomach and intestine, PrPc appears to be concentrated in secretory globules, suggesting a role for PrPc in the secretory function of the digestive tract. The secretory aspect of PrPc may be a key to understanding the physiopathological mechanisms underlying TSE.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410051036
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    A role for vesicles in human basophil secretion (1998)
    Springer
    Cell & tissue research 293 (1998), S. 1-22 
    Details
    ISSN: 1432-0878
    Keywords: Key words Piecemeal degranulation ; Histamine ; Charcot-Leyden crystal protein ; Anaphylactic degranulation ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  The evidence for vesicular transport as a mechanism for secretion by human basophils is reviewed. Initially, direct electron-microscopic inspection of experimentally produced and sequentially biopsied contact allergy skin lesions revealed a unique form of secretion termed piecemeal degranulation, characterized by the slow emptying of secretory granule contents (with retention of empty containers) in the absence of extrusion of entire granules. Budding of small vesicles to/from secretory granules was observed, and cytoplasmic vesicles were abundant. A generalized degranulation model was proposed to unify classical regulated secretion and this new form of secretion. Investigation of the mechanism(s) of secretion from human basophils required the development of numerous tools and resources. Chief among these were: (a) isolation and purification of circulating basophils; (b) identification of specific growth factors to increase the supply of this rare granulocyte; (c) understanding of secretogogue mechanisms and reliable analyses of secreted basophil products; and (d) development of ultrastructural preparations allowing imaging of small vesicles and quantifiable small electron-dense tags for granule materials in small vesicles. Applications of these tools to well-defined models of basophil secretion have established a role for vesicles as a mechanism for effecting secretion of histamine and the Charcot-Leyden crystal protein from activated human basophils.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410051093
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Maturation of rat dendritic cells during intrahepatic translocation evaluated using monoclonal antibodies and electron microscopy (1998)
    Springer
    Cell & tissue research 294 (1998), S. 503-514 
    Details
    ISSN: 1432-0878
    Keywords: Key words Dendritic cells ; Maturation ; Intrahepatic translocation ; Immunohistochemistry ; Electron microscopy ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Specific populations of hepatic sinusoidal cells were stained with monoclonal antibodies that recognize monocytes/macrophages (ED1), tissue macrophages (Kupffer cells) (ED2), MHC class II (Ia) antigen (MRC OX6), and dendritic cells/γ,δ T-cells (MRC OX62) and analyzed by light and electron microscopy. The majority of ED1+ and/or ED2+ cells were localized to the hepatic parenchyma, whereas OX6+ and/or OX62+ cells were more densely distributed within Glisson’s sheath than in the hepatic parenchyma. Double-immunoperoxidase staining of normal liver for ED1, ED2, and OX6 identified dendritic cells (DC) of two different phenotypes, ED1+ED2–OX6+ and ED1–ED2–OX6+. DC can be classified into three different types based on ultrastructural characteristics. The first type (type I) is characterized by one or more long cytoplasmic processes and a well-developed lysosomal system. The second type (type II) has an inconspicuous lysosomal system, abundant hyaloplasm, and characteristic short cytoplasmic processes. The third type (type I–II) has cytologic features intermediate between those of type I and type II DC. At the electron-microscopic level, these three cell types are found in the sinusoidal lumen, whereas the majority of type II DC are located in the space of Disse and Glisson’s sheath. Furthermore, some OX6-labeled elongated DC appeared to traverse the lumen of sinusoids through endothelial pores to enter the space of Disse. One hour after intravenous injection of latex particles (0.81 μm in diameter), numerous latex-laden dendritic cells (ED1+OX6+, type I and type I–II) were detected in the lumen of hepatic sinusoids, but not in the space of Disse or Glisson’s sheath. These findings suggest that normal rat liver contains resident dendritic cells which downregulate phagocytic activity and mature into potent accessory cells during migration from the portal vein toward the central vein. These DC then traverse the sinusoidal lumen to the hepatic lymph system via the space of Disse.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410051201
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Renewing olfactory receptor neurons in goldfish do not require contact with the olfactory bulb to develop normal chemical responsiveness (1997)
    Springer
    Journal of comparative physiology 181 (1997), S. 425-437 
    Details
    ISSN: 1432-1351
    Keywords: Key words Olfactory receptor cells ; Olfactory bulbectomy ; Olfactory axotomy ; Electrophysiology ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract This study investigated whether contact with the olfactory bulb was necessary for developing and renewing olfactory receptor neurons (ORNs) to attain normal odorant responsiveness, and whether the anatomical and functional recoveries of the olfactory epithelium were similar in both bulbectomized (BE) and bilaterally axotomized (AX) preparations. In vivo electrophysiological recordings were obtained in response to amino acids, a bile acid [taurolithocholic acid sulfate(TLCS)] and a pheromonal odorant [17α, 20β,-dihydroxy-4-pregnen-3-one (17,20P)] from sexually immature goldfish. Both transmission and scanning electron microscopy indicated that the olfactory epithelium degenerated in BE and AX goldfish. Within 1–2 weeks subsequent to the respective surgeries, responses to high concentrations (〉0.1 mmol · l−1) of the more stimulatory amino acids remained, whereas responses were no longer obtainable to TLCS and 17,20P. At 4 weeks, responses to amino acid stimuli recovered to control levels, while responses to TLCS and 17,20P were minimal. By 7 weeks post bilateral axotomy, the olfactory epithelium recovered to a condition similar to control sensory epithelium; however, the rate of degeneration and proliferation of receptor neurons in BE preparations appeared to remain in balance, thus blocking further recovery of the olfactory epithelium. At 7 weeks post surgery, odorant responses of AX and BE goldfish to TLCS and 17,20P were still recovering.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s003590050126
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 11
    Electronic Resource
    Electronic Resource
    Neuropeptide Y-immunoreactive intracardiac neurones, granule-containing cells and nerves associated with ganglia and blood vessels in rat and guinea-pig heart (1997)
    Springer
    Cell & tissue research 289 (1997), S. 445-454 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Intracardiac neurones ; Innervation ; Heart ; Neuropeptide Y ; Immunocytochemistry ; Electron microscopy ; Rat (Sprague Dawley) ; Guinea-pig (Dunkin Hartley)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. Intrinsic neuropeptide Y-containing neurones in rat and guinea-pig hearts were studied at the ultrastructural level by the pre-embedding peroxidase-antiperoxidase immunocytochemical technique. Intracardiac neuronal cell bodies were often weakly or moderately immunostained, and the labelling was usually pronounced in the Golgi complex, multivesicular bodies, some cisterns of granular endoplasmic reticulum and large granular vesicles. Neuropeptide Y-immunoreactive nerve fibres were also observed in association with intracardiac neurones. A subpopulation of neuropeptide Y-immunoreactive granule-containing cells in the rat heart are described for the first time and were very heavily labelled; other granule-containing cells were non-immunoreactive, but were contacted by neuropeptide Y-containing nerves. Preterminal regions of nerve fibres that were located in nerve bundles were only weakly neuropeptide Y-immunoreactive, in contrast to the heavy labelling observed in varicosities that contained many synaptic vesicles. Many neuropeptide Y-immunoreactive nerve fibres were associated with the coronary vasculature and were particularly prominent in the walls of small arteries and arterioles where labelled nerve varicosities were present close to the smooth muscle cells. Immunoreactive nerves were also seen in the myocardium, usually near to capillaries. In axonal varicosities, the central core of large granular vesicles was immunolabelled, and electron-dense immunoreactive material outlined the membranes of small and large clear vesicles. The significance of neuropeptide Y-immunoreactive intracardiac neurones and granule-containing cells and the origin of associated labelled nerve fibres in the heart are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410050890
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 12
    Electronic Resource
    Electronic Resource
    Immuno-electron microscopy reveals that the excitotoxin quinolinate is associated with the plasma membrane in human peripheral blood monocytes/macrophages (1997)
    Springer
    Cell & tissue research 290 (1997), S. 633-639 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Quinolinic acid ; Interferon-γ ; Kynurenine ; Electron microscopy ; Immunocytochemistry ; Excitotoxicity ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract.  Quinolinate (QUIN), a tryptophan-derived excitotoxin, was localized ultrastructurally in human peripheral blood monocytes/macrophages (MØ) by immuno-electron microscopy. A combined carbodiimide/glutaraldehyde/paraformaldehyde-based fixation procedure was developed for optimal retention of QUIN in the cell as well as minimal loss of ultrastructure; a silver-enhanced colloidal gold detection system was used for electron-microscopic analysis. Gold particles representing QUIN immunoreactivity were associated with the inner side of the plasma membrane in normal MØ. The number of gold particles increased significantly when QUIN levels were elevated by treatment with its precursor kynurenine, but location of the gold particles remained essentially the same under this condition. Treatment with interferon-γ increased the number of Golgi bodies, vacuoles and pseudopodia, reflecting the activated state of the cell. Significantly increased numbers of gold particles representing QUIN were detectable in approximately the same location as in the case of kynurenine treatment. Combined treatment with kynurenine and interferon-γ maximally increased the number of gold particles at the periphery of the cell. The pseudopodia were intensely stained with gold particles, while they were not detectable in the inner part of the cytoplasm or in any other organelle even under this activated condition. The significance of the specific location of QUIN revealed in the present study and its relation to the release and subsequent actions of QUIN are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410050969
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 13
    Electronic Resource
    Electronic Resource
    Synaptic exocytosis of dense-core vesicles in blue crab (Callinectes sapidus) stomach muscles (1997)
    Springer
    Cell & tissue research 289 (1997), S. 517-526 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Neuromuscular junction ; Synaptic vesicles ; Vesicle fusion ; Electron microscopy ; Callinectes sapidus (Crustacea)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. Neuromuscular terminals of a single motoneuron to four muscles (CPV7a, GM5a, CV2, and CV3) in the stomach of the blue crab Callinectes sapidus showed structural evidence for the exocytotic release of dense-core vesicles exclusively at synapses. The primary evidence was the appearance of dense cores in the synaptic cleft, accompanied by indentations of the presynaptic or postsynaptic membrane. In their simplest form, these consisted of an omega-shaped figure of the presynaptic membrane enclosing one dense core, denoting release of a single dense-core vesicle. A larger indentation of the presynaptic membrane enclosing several dense cores denoted multiple release. A more complex form of multiple release was where the presynaptic membrane was normal, but the postsynaptic membrane elaborated into a sac projecting into the granular sarcoplasm and filled with dense cores. The postsynaptic sac in some instances was compressed into a thin, fingerlike extension, which lacked dense cores and, at its distal end, separated into small cisternae, suggesting a mechanism for membrane recycling. Profiles depicting single and multiple releases of dense-core vesicles were found more frequently at neuromuscular terminals that release relatively large amounts of transmitter with a single stimulus, such as CV2 and CV3, compared to those releasing smaller amounts, such as CPV7a and GM5a. The disparity in release sites among the four muscles of this single motor unit and the fact that many of the multiple-release figures were closely adjacent to the active zones for transmitter release suggest a possible modulatory role for dense-core vesicles in synaptic transmission. Such modulation may be long lasting, as implied by the postsynaptic sacs, which may permit prolonged release of the contents of their dense cores into the synaptic cleft. This is in keeping with the functional role of these stomach muscles, which is to be continuously active for long periods of time.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410050897
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 14
    Electronic Resource
    Electronic Resource
    Immunoreactive excitatory amino acids in the parietal eye of lizards, a comparison with the pineal organ and retina (1997)
    Springer
    Cell & tissue research 287 (1997), S. 275-283 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Parietal eye ; Pineal organ ; Retina ; Glutamate ; Aspartate ; Immunocytochemistry ; Electron microscopy ; Lacerta muralis ; Lacerta agilis ; Lacerta viridis (Lacertilia)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. The fine structure of the organ and the localization of the excitatory amino acids glutamate and aspartate were studied in the parietal eye of lizards by postembedding immunoelectron microscopy. The parietal eye contains cone photoreceptor cells, secondary neurons, and ependymal and lens cells. The photoreceptors form long inner and outer segments, some of them being paired as ”twin-photoreceptors” by zonulae adherentes. Perikarya of neurons bear sensory cilia (containing 9×2+0 pairs of tubules) extending into the intercellular space. No neurohormonal terminals are present in the parietal eye. A higher immunoreactivity to glutamate than to aspartate is found in the photoreceptors and in the secondary neurons of the parietal eye. Glutamate immunogold labeling is more intense in the axonal processes of photoreceptors and neurons and in most of the nerve fibers of the parietal nerve running to the brain stem. Weak aspartate and glutamate immunoreactivity can be detected in the ependymal and lens cells. A similar distribution of immunoreactive amino acids is found in the photoreceptors, secondary neurons, and ependymal glial elements of the pineal organ, and retina of the lateral eye of the same animals. Immunoreactive glutamate accumulates in the axons of photoreceptors and secondary neurons of the parietal eye suggesting that this excitatory amino acid acts as a synaptic mediator in the neural efferentation of the organ. Thus, the efferent light-conducting pathway of the parietal organ is similar to that of the pineal organ and lateral eye retina. As the Mullerian cells of the retina, the ependymal and lens cells of the parietal eye and the ependymal-glial cells of the pineal organ may play a role in the metabolism and/or elimination of excitatory amino acids released by photoreceptors.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410050752
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 15
    Electronic Resource
    Electronic Resource
    Expression of basic fibroblast growth factor-like immunoreactivity in the nuclei of regenerating hepatocytes (1997)
    Springer
    Cell & tissue research 288 (1997), S. 517-527 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Liver ; Subcellular fractions ; Immunohistochemistry ; Electron microscopy ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. This study, utilizing rats subjected to two-thirds partial hepatectomy or sham operation, was designed (1) to investigate the content of basic fibroblast growth factor (bFGF) in the subcellular fractions of regenerating and sham-operated rat livers by immunoblot experiments and enzyme-linked immunosorbent assay (ELISA), (2) to show that bFGF immunoreactivity and proliferating cell nuclear antigen (PCNA) immunoreactivity are markers for hepatocellular mitosis before and after partial hepatectomy, and (3) to observe the location and fine structure of the bFGF immunoreaction within the regenerating liver with special attention to bFGF immunoreactivity in the nuclei of regenerating hepatocytes. Immunoblot experiments and ELISA showed a transient increase in high-molecular-weight forms of bFGF in the nuclear subcellular fraction of regenerating liver 48 h after partial hepatectomy. By light microscopy, bFGF and PCNA immunoreactivities were detected in the nuclei of regenerating hepatocytes. Electron microscopy demonstrated bFGF-like immunoreactivity mainly in the nuclear euchromatin and rarely in the heterochromatin or nucleoli of regenerating hepatocytes. The transient increase in high-molecular-weight forms of bFGF in the nuclear euchromatin of regenerating hepatocytes, together with the concomitant expression of PCNA in the regenerating liver, suggests an important role of the high-molecular-weight forms of bFGF in hepatocyte proliferation and/or mitosis, although authentic bFGF with a molecular form of 18 kDa is not considered to be involved in hepatic regeneration.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410050837
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 16
    Electronic Resource
    Electronic Resource
    Desmin filaments in the electrocytes of the electric organ of the electric eel Electrophorus electricus (1996)
    Springer
    Cell & tissue research 285 (1996), S. 387-393 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Electrocyte ; Intermediate filaments ; Desmin ; Cytoskeleton ; Electron microscopy ; Electrophorus electricus (Teleostei)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. Desmin protein is an abundant constituent of the intermediate filaments in the electrocytes of the electric organ of the electric eel Electrophorus electricus. Polyclonal antibodies were raised against purified desmin from the electric organ and used for immunolabeling of the protein in reconstituted filaments. In thick sections of the main electric organ that has been stained with fluorescein-labeled desmin-specific antibodies, light microscope revealed a diffuse meshwork of desmin filaments dispersed in the cytoplasm of electrocytes. In the region under the membrane, the immunostaining was slightly more intense than elsewhere. The meshwork of intermediate filaments composed of desmin was examined by electron microscopy of the main electric organ. Immuno-gold labeling demonstrated a widespread meshwork of desmin filaments in the cytoplasm and in close association with the plasma membrane. These observations suggest that intermediate filaments play a role in the maintenance of the morphology of electrocytes and, as an intracellular meshwork spanning the width of the cell, they may contribute to the organization of the intracellular compartments.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410050654
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 17
    Electronic Resource
    Electronic Resource
    Nitric oxide synthase-containing neurones and nerve fibres within cardiac ganglia of rat and guinea-pig: an electron-microscopic immunocytochemical study (1996)
    Springer
    Cell & tissue research 284 (1996), S. 19-28 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Innervation ; Heart ; Intracardiac neurone ; Nitric oxide ; Immunocytochemistry ; Electron microscopy ; Rat (Sprague Dawley) ; Guinea-pig (Dunkin Hartley)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. The nitric oxide synthase-immunoreactivity and NADPH-diaphorase activity of intracardiac neurones in the rat and guinea-pig was studied at the ultrastructural level. While some nitric oxide synthase-containing intracardiac neurones were very heavily labelled, with electron-dense immunoprecipitate distributed throughout the neuronal cell bodies and their processes, most of the labelled neurones exhibited a lighter and more patchy distribution of nitric oxide synthase-immunoreactive material. Synapses made by nitric oxide synthase-negative nerve fibres with labelled intracardiac neurones were seen. Conversely, many nitric oxide synthase-containing nerve fibres that made synaptic contacts with unlabelled intracardiac neurones were also observed. Some small granule-containing cells were nitric oxide synthase-immunoreactive and were associated with unlabelled nerve terminals, while non-immunoreactive small granule-containing cells that were innervated by nitric oxide synthase-immunoreactive nerves were also seen. Small patches of osmiophilic electron-dense material were observed in the cytoplasm of NADPH-diaphorase-positive intracardiac neurones. This is the first description of the ultrastructural distribution of nitric oxide synthase-immunoreactivity and NADPH-diaphorase activity in a subpopulation of intracardiac neurones of rat and guinea-pig heart and provides further evidence in support of a role for nitric oxide in the local control of the heart by intrinsic neurones.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410050563
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 18
    Electronic Resource
    Electronic Resource
    Studies on the structure of ocellar photoreceptor cells of Drosophila melanogaster with special reference to subrhabdomeric cisternae (1996)
    Springer
    Cell & tissue research 284 (1996), S. 77-85 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Ocellus ; Photoreceptor cells ; Retinal degeneration ; Subrhabdomeric cisternae ; Electron microscopy ; Immuno-electron microscopy ; Phosphatidylinositol transfer protein ; Drosophila melanogaster (Insecta)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. We studied the structure of ocellar photoreceptor cells of Drosophila melanogaster, particularly the subrhabdomeric cisternae which our previous studies have shown to be essential structures for turnover of photoreceptive membranes in compound eyes. Each ocellus contained elongated photoreceptor cells with rhabdomeres positioned distally. In the subrhabdomeric regions, endocytotic invaginations were frequently observed, suggesting active turnover of photoreceptive membranes. In the vicinity of the photoreceptive microvilli, membranous structures similar to the subrhabdomeric cisternae in compound eyes were observed. These membranous structures were immunopositive for the rdgB protein, a phosphatidylinositol transfer protein that is localized to the subrhabdomeric cisternae in compound eyes. The ocellar photoreceptor cells of the retinal degeneration mutants (rdgA,B) were also studied. In these mutants, retinal degeneration has been reported to start, in compound eyes, with the disappearance of the subrhabdomeric cisternae. We found that the ocellar subrhabdomeric cisternae also disappear during the initial stage of retinal degeneration. From these observations, we conclude that the mechanism of photoreceptive membrane turnover in ocellar photoreceptor cells involves the rdgB and probably the rdgA proteins which are associated with subrhabdomeric cisternae, as is the case for photoreceptive membrane turnover in compound eyes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410050568
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 19
    Electronic Resource
    Electronic Resource
    Chordotonal sensilla embedded in the epidermis of the soft integument of the cricket, Teleogryllus commodus (1996)
    Springer
    Cell & tissue research 284 (1996), S. 125-142 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Chordotonal organ ; Scolopidium ; Mechanoreceptor ; Sensilla ; Electron microscopy ; Phylogenesis ; Teleogryllus commodus (Insecta)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. More than 50 chordotonal sensilla, or scolopidia, embedded entirely in the integument were found in each side of the genital chamber wall in the female cricket, Teleogryllus commodus. Their cell bodies lie among the epidermal cells, and the tips of their dendrites terminate in the cuticle. About half of them contain two sensory cells (two-cell scolopidium), the others only one (one-cell scolopidium). The sensory cell in the one-cell scolopidium is the type-1 cell. In the two-cell scolopidium one is type-1 and the other type-2. Regardless of the number of sensory cells, they are all amphinematic. In the two-cell scolopidium only the type-2 dendrite, rich in microtubules, penetrates into the cuticle, bifurcates and terminates in the tube enclosed by an attachment cell; the type-1 never extends into the cuticle. On the other hand, the type-1 cell in the one-cell scolopidium projects its apex into the cuticle. The unique topography and structure of these scolopidia lead to the following hypothesis about the phylogenetic relationship between the scolopidia and other kinds of sensilla: the type-1 scolopidial sensory cell buried in the integument may be the original model, which through the loss of the long regular axoneme has given rise to type-2 cells. Modification of the apical region, the tubular body or ramification, may have lead to the cuticular sensilla corresponding to the development of the cuticular apparatus, and the scolopidia may have been withdrawn into the body cavity to form ordinary chordotonal organs.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410050573
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 20
    Electronic Resource
    Electronic Resource
    The effect of the illumination time when treating port-wine stains (1995)
    Springer
    Lasers in medical science 10 (1995), S. 93-104 
    Details
    ISSN: 1435-604X
    Keywords: Copper vapour laser ; Electron microscopy ; Illumination time ; Numerical modelling ; Optimal treatment ; Port-wine stain
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Physics , Technology
    Notes: Abstract This paper reports the electron microscopy results obtained from two patients who were treated with 5 W of yellow (578 nm) light from a copper vapour laser with an illumination time of 3.6 ms and a 0.3 mm spot diameter. The endpoint of treatment was transient blanching. Following treatment, erythema was observed. There was minimal damage to the epidermis and non-vascular tissue such as the nerve fibres. There was severe damage to the endothelial cells of the ectatic vessels. Twenty-four hours after treatment, platelet activation and collagen were present, indicating that these vessels were no longer viable. Theoretical calculations are used to determine the flow of heat within and away from a 50μm diameter vessel. From this, heating of the entire vessel is shown to occur with illumination times of 4 ms, with minimal heating of the non-vascular tissue. Shorter illuminations do not heat the entire vessel, while the use of longer illumination times will cause excessive damage to the surrounding non-vascular tissue. Illumination times close to 4 ms must be regarded as optimal.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02150846
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 21
    Electronic Resource
    Electronic Resource
    The anatomy of bone sialoprotein immunoreactive sites in bone as revealed by combined ultrastructural histochemistry and immunohistochemistry (1995)
    Springer
    Calcified tissue international 57 (1995), S. 277-284 
    Details
    ISSN: 1432-0827
    Keywords: Bone sialoprotein ; osteoblast ; Bone matrix ; Electron microscopy ; Immunolocalization ; noncollagenous protein
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Abstract Bone sialoprotein was immunolocalized at the EM level in thin Lowicryl K4M sections of rat bone. Because of the unconventional EM morphology of the bone matrix seen in thin demineralized acrylate sections, the pattern of immunolabeling was compared with detailed structural images of demineralized bone obtained using an en bloc treatment of tissue samples with the cationic electron ‘dye’, Malachite Green (MG), which provides stabilization and retention of anionic material throughout specimen processing. A system of structures corresponding to the sites of bone sialoprotein (BSP) immunoreactivity, as seen in Lowicryl K4M thin sections, could be readily identified in the MG-treated, expoxy thin sections. This system includes the cement lines, and aggregates of similar material within mineralized bone and mineralizing osteoid. The virtual identity of BSP distribution with the arrangement of the MG-visualized material indicates that a BSP-enriched, noncollagenous phase can be demonstrated using different, unrelated tissue preparation and imaging protocols for EM. Besides improving our understanding of the distribution of bone sialoprotein in bone, these data assign a previously unrecognized structural dimension to noncollagenous material in the bone matrix.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00298883
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 22
    Electronic Resource
    Electronic Resource
    An ultrastructural evaluation of the effects of cysteine-proteinase inhibitors on osteoclastic resorptive functions (1995)
    Springer
    Calcified tissue international 56 (1995), S. 566-570 
    Details
    ISSN: 1432-0827
    Keywords: Cathepsin inhibitors ; Osteoclasts ; Resorption ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Abstract This study was designed to evaluate the effects of specific and potent cathepsin inhibitors on osteoclastic resorptive functions in vitro by means of a novel ultrastructural assay system. Mouse bone marrow cell-derived osteoclasts were suspended on dentine slices and cultured for 48 hours in the presence of either E-64 (a generalized cysteine proteinase inhibitor) or Z-Phe-Phe-CHN2 (a selective cathepsin L inhibitor). After the removal of cultured osteoclasts, co-cultured dentine slices were examined using electron microscopy: backscattered (BSEM), scanning (SEM), and atomic force (AFM). In morphometric analyses of BSEM images, there were no significant differences in the areas of demineralized dentine surfaces between control and inhibitor-treated groups, suggesting that cathepsin inhibitors had no effect on dentine demineralization by cultured osteoclasts. However, in SEM and AFM observations, both inhibitors remarkably reduced to the same extent, the formation of deep resorption lacunae on dentine slices that had resulted from degradation of matrix collagen. In addition, Z-Phe-Phe-CHN2 treatment produced deeper, ring-like grooves with little collagen exposure in shallow resorption lacunae. These results strongly suggest that (1) cathepsins released by osteoclasts are involved in the formation of deep resorption lacunae, and (2) cathepsin L plays a key role in bone resorption.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00298591
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 23
    Electronic Resource
    Electronic Resource
    Horseradish peroxidase in axons of the dorsal funiculi of the cat: distribution after an injection of the enzyme into the dorsal column nuclei (1995)
    Springer
    Cell & tissue research 283 (1995), S. 67-73 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Node of Ranvier ; Axon ; Horseradish peroxidase (HRP) ; Retrograde axonal transport ; Electron microscopy ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. Horseradish peroxidase (HRP) was injected into the left dorsal column nuclei of adult cats. Large dorsal funiculi axons of the C3, C5, C8 and L7 segments were searched for HRP-activity after 12, 24, 36 and 48 h using light and electron microscopy. Accumulations of intra-axonal HRP-positive bodies occurred at nodes of Ranvier in the C3–C8 segments at 12, 24 and 36 h and in the L7 segments at 24, 36, and 48 h. The accumulations of HRP in three spatio-temporally different consecutive patterns, noted earlier at nodes of Ranvier in the peripheral nervous system (PNS) portion of feline alpha motor axons for more than 70 h after an intramuscular injection of the enzyme, were not observed in the present material. We suggest that the differences in the modes in which large PNS and CNS axons interact with retrogradely transported HRP are due to differences in the organization of the respective nodal regions. We also emphasize that endocytosis via axon terminals in the CNS normally represents uptake of material from an extracellular space which is controlled and protected by the blood-brain barrier. This is in contrast to endocytosis via axon terminals in a muscle, which represents uptake of material from an extracellular space openly exposed to influx of different substances from the blood stream.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410050513
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 24
    Electronic Resource
    Electronic Resource
    FMRFamide-like and allatostatin-like immunoreactivity in the lateral heart nerve of Periplaneta americana: colocalization at the electron-microscopic level (1995)
    Springer
    Cell & tissue research 282 (1995), S. 69-80 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Lateral heart nerve ; FMRFamide ; Allatostatin ; Coexistence ; Mirror-section ; Axosomatic synapses ; Electron microscopy ; Periplaneta americana (Insecta)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. Both allatostatin immunoreactivity (AS-IR) and FMRFamide immunoreactivity (FMRFa-IR) have been demonstrated light-microscopically in the lateral heart nerve of Periplaneta americana. The identical labeling of some fibers suggests the coexistence of the two antigens. Electron-microscopically, six granule types in the peripheral part of the lateral heart nerve can be distinguished according to their size and density (types 1–6). These granule types can be subdivided immunocytochemically by means of a new mirror-section technique. Granules of types 4 and 5 always exclusively show FMRFa-IR. In the populations of fibers containing granules of types 1 and 6, axon profiles can be found that contain granules colocalizing FMRFa-IR and AS-IR. Other axon profiles of these populations only contain immunonegative granules of the same ultrastructure. Granules of type 2 can be differentiated immunocytochemically in three forms in the same section: In some fibers, they are nonreactive; in other fibers of the same section, they show FMRFa – IR, whereas in a third fiber type, granules show AS – IR. Finally, granules of type 3 can be observed with FMRFa-IR. In other fibers, they occur with the same ultrastructure but exhibit no immunoreactivity. Two soma types occur in the lateral heart nerve. Soma type I is characterized by the production of electron-dense granules that show FMRFa-IR. Type II is in close contact with various fibers, forming different types of axosomatic synapses, hitherto unknown in Insecta.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410050460
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 25
    Electronic Resource
    Electronic Resource
    Electron-microscopic localisation of thiol and disulphide groups by direct monomaleimido-nanogold labelling in the spermatozoa of a marsupial, the tammar wallaby (Macropus eugenii) (1995)
    Springer
    Cell & tissue research 282 (1995), S. 291-296 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Spermatozoa ; Acrosome ; Thiols ; Disulphides ; Electron microscopy ; Monomaleimido nanogold ; Macropus eugenii (Marsupialia)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. This study utilised a commercially available monomaleimido-nanogold reagent to directly label cellular thiol groups (SH) of marsupial (tammar wallaby) spermatozoa before and after reduction of disulphides (S-S) with mercaptoethylamine hydrochloride (MEA). The sperm surface, mitochondrial membranes, axoneme and tail fibres were all labelled with gold particles before MEA treatment and the label intensity was increased after S-S reduction. The acrosomal membranes and matrix of spermatozoa contained no detectable SH prior to MEA treatment. However, after moderate MEA treatment (1 mg/ml) gold label was associated with the acrosomal membrane and invaginated acrosomal membrane within the acrosomal matrix. After exposure to 5 and 10 mg/ml MEA, gold particles heavily labelled the acrosomal matrix. Thus, the acrosomal membranes and matrix of tammar wallaby spermatozoa both contain S-S cross-linked structures, and this may contribute to the unusual stability of the marsupial acrosome. Under all treatment conditions the nucleus remained unlabelled. This is consistent with early studies which indicated that cysteine was absent from the nuclear protamines. The study also demonstrated that monomaleimido-nanogold can be used to resolve SH- and S-S-rich cellular structures directly, in addition to its use to label antibodies and Fab fragments for immunochemical localisation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410050480
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 26
    Electronic Resource
    Electronic Resource
    Dynamics of secretory granules in somatotrophs of rats after stimulation with growth hormone-releasing factor: a stereological analysis (1995)
    Springer
    Cell & tissue research 282 (1995), S. 493-501 
    Details
    ISSN: 1432-0878
    Keywords: Somatotrophs ; Growth hormone ; Growth hormone-releasing factor ; Secretory granule ; Electron microscopy ; Morphometry ; Rat (Fischer 344)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The anterior pituitary tissue of male rats injected with growth hormone-releasing factor (GRF) was either processed for stereology at the light-and electron-microscopic levels, or homogenized for growth hormone (GH) assay 2–60 min after GRF injection. Secretory granules of somatotrophs became smaller but increased in numerical density 2 min after GRF injection. Their volume density began to increase at 5 min. The frequency of exocytosis of the granules was most prominent as early as 2 min after GRF injection and reduced thereafter. GH levels in the tissue were lowest at 2–5 min, and returned to the control value by 60 min. Serum GH levels were highest at 15 min; even at 60 min, this value was higher than in the controls. These findings suggest that secretory granules in somatotrophs are stimulated to divide by GRF, resulting in a decrease in size and an increase in number. The discrepancy between the earlier formation of new secretory granules and the later restoration of intracellular GH levels implies that GRF first stimulates the synthesis of constituents of granules other than GH, and only later the synthesis of GH, and that newly formed small secretory granules contain less GH. From the clearance rate of serum GH and the frequency of granule exocytosis, it can be estimated that about a half million granules are released to maintain 1 ng/ml of serum GH in rats.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00318881
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 27
    Electronic Resource
    Electronic Resource
    Decreased adhesion of oxidized LDL-stimulated platelets caused by cytochalasin D (1995)
    Springer
    Cell & tissue research 280 (1995), S. 183-188 
    Details
    ISSN: 1432-0878
    Keywords: Blood platelets ; Oxidized LDL ; Cytochalasin D ; Reflection contrast microscopy ; Image analysis ; Electron microscopy ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The adhesion of human blood platelets is studied with an in vitro model using reflection contrast microscopy and an image analysis system. The adhesive feature is promoted by oxidatively modified low density lipoprotein, which also induces functional morphological changes of platelets. However, when washed platelets are pretreated with 0.05 mM cytochalasin D, oxidized low density lipoprotein (100 μg/ml) causes a slower increase of the adhesion area (11.6 μm2/min) compared to untreated platelets (15.7 μm2/min) or platelets treated by oxidized low density lipoprotein alone (20.5 μm2/min, P〈0.01). These results are supported by light transmission analysis and by transmission electron microscopy. Our experiments suggest that cytochalasin D inhibits the change of platelets in shape induced by oxidized low density lipoprotein, hinders the adhesion, but does not prevent the adhesion entirely.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00304523
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 28
    Electronic Resource
    Electronic Resource
    Do vasoactive intestinal peptide (VIP)-and nitric oxide synthase-immunoreactive terminals synapse exclusively with VIP cell bodies in the submucous plexus of the guinea-pig ileum? (1995)
    Springer
    Cell & tissue research 281 (1995), S. 485-491 
    Details
    ISSN: 1432-0878
    Keywords: Nitric oxide synthase ; Vasoactive intestinal peptide ; Immunohistochemistry ; Electron microscopy ; Submucous plexus ; Guinea-pig
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract In the submucous plexus of the guinea-pig ileum, previous light-microscopic studies have revealed that vasoactive intestinal peptide (VIP)-immunoreactive and nitric oxide synthase (NOS)-immunoreactive terminals are found predominantly in association with VIP-immunoreactive nerve cell bodies. In this study, double-label immunohistochemistry at the light-microscopic level demonstrated co-localization of NOS-immunoreactivity and VIP-immunoreactivity in axon terminals in submucous ganglia. About 90% of nerve fibres with NOS-immunoreactivity or VIP-immunoreactivity were immunoreactive for both antigens; only about 10% of labelled varicosities contained only NOS-immunoreactivity or VIP-immunoreactivity. The VIP/NOS varicosities were more often seen in the central parts of the ganglia, close to the VIP-immunoreactive cell bodies. Ultrastructural immunocytochemistry with antibodies to VIP was used to determine if NOS/VIP terminals synapse exclusively with VIP-immunoreactive nerve cell bodies. We examined the targets of VIP-immunoreactive boutons in two submucous ganglia from different animals. Serial ultrathin sections were taken through the ganglia after they had been processed for VIP immunocytochemistry. For each cell body, the number of VIP inputs (synapses and close contacts) was determined. The number of VIP-immunoreactive synapses received by the cell bodies of submucous neurons varied from 0–4 and the number of VIP-immunoreactive close contacts varied from 3–10. There was no significant difference between VIP-immunoreactive nerve cell bodies and non-VIP nerve cell bodies in the number of VIP-immunoreactive synapses and close contacts they received. Thus, the implication from light microscopy that NOS/VIP terminals end predominantly on VIP nerve cells was not vindicated by electron microscopy.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00417865
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 29
    Electronic Resource
    Electronic Resource
    Localization of CD44, the hyaluronate receptor; on the plasma membrane of osteocytes and osteoclasts in rat tibiae (1995)
    Springer
    Cell & tissue research 280 (1995), S. 225-233 
    Details
    ISSN: 1432-0878
    Keywords: CD44, adhesion molecule ; Bone ; Osteoclasts ; Osteocytes ; Immunohistochemistry ; Confocal laser scanning microscopy ; Electron microscopy ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract CD44 is a multifunctional adhesion molecule that binds to hyaluronic acid, type I collagen, and fibronectin. We have studied the immunohistochemical localization of CD44 in bone cells by confocal laser scanning microscopy and transmission electron microscopy in order to clarify its role in the cell-cell and/or cell-matrix interaction of bone cells. In round osteoblasts attached to bone surfaces, immunoreactivity is restricted to their cytoplasmic processes. On the other hand, osteocytes in bone matrices show intense immunoreactivity on their plasma membrane. Intense immunoreactivity for CD44 can be detected on the basolateral plasma membranes of osteoclasts. There is considerably less reactivity observed in the area of the plasma membrane that is in direct contact with bone. The pre-embedding electron-microscopical method has revealed that CD44 is mainly localized on the basolateral plasma membrane of osteoclasts. However, the ruffled border and clear zone show little immunoreactivity. A CD44-positive reaction can be detected on both plasma membranes in the contact region between osteoclasts and osteocytes. These findings suggest that: 1) cells of the osteoblast lineage express CD44 in accordance with their morphological changes from osteoblasts into osteocytes; 2) osteoclasts express CD44 on their basolateral plasma membrane; 3) CD44 in osteoclasts and osteocytes may play an important role in cell-cell and/or cell-matrix attachment via extracellular matrices.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00307793
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 30
    Electronic Resource
    Electronic Resource
    Ultrastructural investigation of nitric oxide synthase-immunoreactive nerves associated with coronary blood vessels of rat and guinea-pig (1995)
    Springer
    Cell & tissue research 280 (1995), S. 575-582 
    Details
    ISSN: 1432-0878
    Keywords: Nitric oxide synthase ; Coronary vasculature ; Electron microscopy ; Immunocytochemistry Rat (sprague Dawley) ; Guinea-pig (Dunkin Hartley)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Ultrastructural investigation of nitrix oxide synthase-immunoreactive nerves closely associated with blood vessels in rat and guinea-pig hearts revealed many labelled nerve fibres in the walls of the main branches of the coronary arteries, and in arterioles, capillaries and post-capillary venules. The number of nitric oxide synthase-containing nerve fibres associated with different vessels, even those of the same calibre, varied. Terminal regions of nitric oxide synthase-immunoreactive fibres were observed in the endocardium and myocardium. Nitric oxide synthase-labelled fibres displayed electrondense immunoproduct in both varicose and intervaricose regions. Immunoreactive axonal varicosities contained both small and large synaptic vesicles. The characteristics of the nitric oxide synthase-immunoreactive nerve fibres observed in the heart and the possibility that these fibres represent the processes of intracardiac neurones and/or sensory neurones of extrinsic origin are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00318361
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 31
    Electronic Resource
    Electronic Resource
    Ultrastructural study of periodic lamellar granules in human neutrophils (1995)
    Springer
    Cell & tissue research 281 (1995), S. 69-76 
    Details
    ISSN: 1432-0878
    Keywords: Periodic lamellar granule ; Primary granule ; Chronic myeloproliferative disorder ; Neutrophils ; Electron microscopy ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Granules consisting of periodically arranged membranous lamellae and amorphous electron-opaque material, i.e., periodic lamellar granules, are present in human neutrophils. To date, no extensive ultrastructural studies have been carried out on these granules because of their infrequent presence in neutrophils. The bone marrow of 18 cases of chronic myeloproliferative disorders, including one case of chronic neutrophilic leukemia in which periodic lamellar granules were frequently seen in neutrophils, was investigated by electron microscopy. Periodic lamellar granules were seen in neutrophils in 12 of the 18 cases at varying frequencies. They were preferentially seen in immature neutrophils. The transverse profiles of these granules revealed concentric complete/incomplete rings or periodic parallel straight lines, i.e., various patterns of lamellar arrangement were present. Periodic lamellar granules were positive for myeloperoxidase and lysozyme at the electron-microscopic level. These results suggest that these granules represent a primary neutrophil granule subtype. However, their functional and pathologic significance remains unknown.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00307959
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 32
    Electronic Resource
    Electronic Resource
    Investigation of the structural and functional features of splenic ellipsoids in rainbow trout (Oncorhynchus mykiss) (1995)
    Springer
    Cell & tissue research 279 (1995), S. 469-474 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Ellipsoids ; Spleen ; Electron microscopy ; Fluorescent microspheres ; Oncorhynchus mykiss (Teleostei)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. The ultrastructure of ellipsoids in the spleen of rainbow trout (Oncorhynchus mykiss) is described. The endothelium of terminations of arterioles bulged into the lumen, and gaps between the endothelial cells were evident. A continuous basal lamina was not present, and there were extensive interdigitations between the endothelial cells and surrounding reticular cells. The interdigitating processes were rich in microfilaments. Intravenously injected colloidal carbon, approximately 0.03 μm in diameter, was held in the reticular matrix of the ellipsoidal wall and taken up by macrophages that extended cellular processes among the reticular and endothelial cells. The intravenous injection of fluorescent polystyrene microspheres of known diameter showed that microspheres with a diameter of 0.5 or 1.0 μm were localised in the red pulp, whereas microspheres with a diameter of 0.15 μm were retained in ellipsoidal walls. Thus, the terminations of splenic arterioles in rainbow trout were found to be consistent with descriptions of ellipsoids in other vertebrates in that they possessed a specialised cuboidal endothelium, lacked a continuous basal lamina, were surrounded by a sheath of macrophages and reticular cells, and had a role in the selective filtration and retention of blood-borne particles.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410050307
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 33
    Electronic Resource
    Electronic Resource
    FMRFamide-like and allatostatin-like immunoreativity in the lateral heart nerve of Periplaneta americana: Colocalization at the electron-microscopic level (1995)
    Springer
    Cell & tissue research 282 (1995), S. 69-80 
    Details
    ISSN: 1432-0878
    Keywords: Lateral heart nerve ; FMRFamide ; Allatostatin ; Coexistence ; Mirror-section ; Axosomatic synapses ; Electron microscopy ; Periplaneta americana (Insecta)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Both allatostatin immunoreactivity (AS-IR) and FMRFamide immunoreactivity (FMRFa-IR) have been demonstrated light-microscopically in the lateral heart nerve of Periplaneta americana. The identifical labeling of some fibers suggests the coexistence of the two antigens. Electron-microscopically, six granule types in the peripheral part of the lateral heart nerve can be distinguished according to their size and density (types 1–6). These granule types can be subdivided immunocytochemically by means of a new mirror-section technique. Granules of types 4 and 5 always exclusively show FMRFa-IR. In the populations of fibers containing granules of types 1 and 6, axon profiles can be found that contain granules colocalizing FMRFa-IR and AS-IR. Other axon profiles of these populations only contain immunonegative granules of the same ultrastructure. Granules of type 2 can be differentiated immunocytochemically in three forms in the same section: In some fibers, they are nonreactive; in other fibers of the same section, they show FMRFa-IR, whereas in a third fiber type, granules show AS-IR. Finally, granules of type 3 can be observed with FMRFA-IR. In other fibers, they occur with the same ultrastructure but exhibit no immunoreactivity. Two soma types occur in the lateral heart nerve. Soma type I is characterized by the production of electron-dense granules that show FMRFa-IR. Type II is in close contact with various fibers, forming different types of axosomatic synapses, hitherto unknown in Insecta.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00319134
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 34
    Electronic Resource
    Electronic Resource
    Catecholaminergic innervation of the suprachiasmatic nucleus in the adult rat: ultrastructural relationships with neurons containing vasoactive intestinal peptide or vasopressin (1995)
    Springer
    Cell & tissue research 280 (1995), S. 87-96 
    Details
    ISSN: 1432-0878
    Keywords: Suprachiasmatic nucleus ; Catecholamines ; Dopamine ; Electron microscopy ; Vasoactive intestinal peptide ; Vasopressin ; Rat (Sprague Dawley)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Catecholaminergic fibers in the suprachiasmatic nucleus of adult rats were investigated by use of light- and electron-microscopic immunocytochemistry. The suprachiasmatic nucleus receives a modest density of tyrosine hydroxylase-containing axons, homogeneously distributed in the nucleus and forming varicosities throughout its entire rostro-caudal extension. Immunolabeling with antibodies against dopamine showed that this catecholamine input comprises a dopaminergic component. Many tyrosine hydroxylase-positive cells were localized at the immediate periphery of the suprachiasmatic nucleus. With electron-microscopic examination, dendrites of these neurons were found within the limits of the nucleus as well as at a border zone between the suprachiasmatic nucleus proper and the optic tract where they received unlabeled synapses, providing a morphological support for a possible role of dopaminergic neurons in the integration and/or transfer of light-related signals. More than 91% of catecholaminergic axonal varicosities were found to establish morphologically defined synapses with dendrites. To investigate whether these synapses might be shared with neurons of one or both of the two main peptidergic populations of the nucleus, namely vasoactive intestinal peptide- and vasopressin-containing neurons, we carried out doublelabeling experments combining immunoperoxidase and immunogold-silver labeling. Results showed only a few cases of direct association of the catecholaminergic terminals with these peptidergic categories. In both types of dually stained sections, catecholaminergic synapses were preferentially made with unlabeled dendrites. The homogeneous distribution of tyrosine hydroxylase-immunoreactive fibers in the suprachiasmatic nucleus could therefore reflect a lack of significant catecholaminergic innervation of both vasoactive intestinal peptide- and vasopressin-synthesizing neurons.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00304514
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 35
    Electronic Resource
    Electronic Resource
    Origin and destination of globules and irregular masses in the gonadotropin cells from the pituitary of the African catfish, Clarias gariepinus: a morphological study (1995)
    Springer
    Cell & tissue research 280 (1995), S. 113-122 
    Details
    ISSN: 1432-0878
    Keywords: Pituitary ; Gonadotrops ; Crinophagy ; Electron microscopy ; Enzyme cytochemistry ; Immunocytochemistry ; Autoradiography ; Catfish, Clarias gariepinus (Teleostei)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The possible function of globules and irregular membrane-bound masses in the gonadotropin cells of the pituitary of Clarias gariepinus was studied. Strong secretory stimulation led to the disappearance of the secretory granules from gonadotropin cells but globules and irregular masses remained present. Acid phosphatase was detected enzyme-cytochemically in both globules and irregular masses. Radiolabelling with tritiated amino acids followed by autoradiography demonstrated that globules received radioactive material after secretory granules. The latter received radioactive material within 75 min of administration of radioactive amino acids but globules and irregular masses did not. Although some globules became radioactively labelled within 24 h of the administration of radioactive amino acids, irregular masses remained unlabelled during this period. Secretory granules reacted positively with antisera against α and β gonadotropin subunits, whereas globules and irregular masses only reacted with the antiserum against the β subunit. A moderate anti-7B2 immunoreactivity was demonstrated in secretory granules and globules, whereas irregular masses labelled strongly. The combined cytological results indicate that globules and irregular masses are degradative, possibly crinophagic structures which develop by fusional events from secretory granules to globules and then to irregular masses.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00304516
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 36
    Electronic Resource
    Electronic Resource
    Origin and destination of globules and irregular masses in the gonadotropin cells from the pituitary of the African catfish, Clarias gariepinus:a morphological study (1995)
    Springer
    Cell & tissue research 280 (1995), S. 113-122 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Pituitary ; Gonadotrops ; Crinophagy ; Electron microscopy ; Enzyme cytochemistry ; Immunocytochemistry ; Autoradiography ; Catfish ; Clarias gariepinus (Teleostei)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. The possible function of globules and irregular membrane-bound masses in the gonadotropin cells of the pituitary of Clarias gariepinus was studied. Strong secretory stimulation led to the disappearance of the secretory granules from gonadotropin cells but globules and irregular masses remained present. Acid phosphatase was detected enzyme-cytochemically in both globules and irregular masses. Radiolabelling with tritiated amino acids followed by autoradiography demons trated that globules received radioactive material after secretory granules. The latter received radioactive material within 75 min of administration of radioactive amino acids but globules and irregular masses did not. Although some globules became radioactively labelled within 24 h of the administration of radioactive amino acids, irregular masses remained unlabelled during this period. Secretory granules reacted positively with antisera against α and β gonadotropin subunits, whereas globules and irregular masses only reacted with the antiserum against the β subunit. A moderate anti-7B2 immunoreactivity was demonstrated in secretory granules and globules, whereas irregular masses labelled strongly. The combined cytological results indicate that globules and irregular masses are degradative, possibly crinophagic structures which develop by fusional events from secretory granules to globules and then to irregular masses.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00304516
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 37
    Electronic Resource
    Electronic Resource
    Decreased adhesion of oxidized LDL-stimulated platelets caused by cytochalasin D (1995)
    Springer
    Cell & tissue research 280 (1995), S. 183-188 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Blood platelets ; Oxidized LDL ; Cytochalasin D ; Reflection contrast microscopy ; Image analysis ; Electron microscopy ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. The adhesion of human blood platelets is studied with an in vitro model using reflection contrast microscopy and an image analysis system. The adhesive feature is promoted by oxidatively modified low density lipoprotein, which also induces functional morphological changes of platelets. However, when washed platelets are pretreated with 0.05 mM cytochalasin D, oxidized low density lipoprotein (100 μg/ml) causes a slower increase of the adhesion area (11.6 μm2/min) compared to untreated platelets (15.7 μm2/min) or platelets treated by oxidized low density lipoprotein alone (20.5 μm2/min, P〈0.01). These results are supported by light transmission analysis and by transmission electron microscopy. Our experiments suggest that cytochalasin D inhibits the change of platelets in shape induced by oxidized low density lipoprotein, hinders the adhesion, but does not prevent the adhesion entirely.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00304523
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 38
    Electronic Resource
    Electronic Resource
    Catecholaminergic innervation of the suprachiasmatic nucleus in the adult rat: ultrastructural relationships with neurons containing vasoactive intestinal peptide or vasopressin (1995)
    Springer
    Cell & tissue research 280 (1995), S. 87-96 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Suprachiasmatic nucleus ; Catecholamines ; Dopamine ; Electron microscopy ; Vasoactive intestinal peptide ; Vasopressin ; Rat (Sprague Dawley)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. Catecholaminergic fibers in the suprachiasmatic nucleus of adult rats were investigated by use of light- and electron-microscopic immunocytochemistry. The suprachiasmatic nucleus receives a modest density of tyrosine hydroxylase-containing axons, homogeneously distributed in the nucleus and forming varicosities throughout its entire rostro-caudal extension. Immunolabeling with antibodies against dopamine showed that this catecholamine input comprises a dopaminergic component. Many tyrosine hydroxylase-positive cells were localized at the immediate periphery of the suprachiasmatic nucleus. With electron-microscopic examination, dendrites of these neurons were found within the limits of the nucleus as well as at a border zone between the suprachiasmatic nucleus proper and the optic tract where they received unlabeled synapses, providing a morphological support for a possible role of dopaminergic neurons in the integration and/or transfer of light-related signals. More than 91% of catecholaminergic axonal varicosities were found to establish morphologically defined synapses with dendrites. To investigate whether these synapses might be shared with neurons of one or both of the two main peptidergic populations of the nucleus, namely vasoactive intestinal peptide- and vasopressin-containing neurons, we carried out double-labeling experiments combining immunoperoxidase and immunogold-silver labeling. Results showed only a few cases of direct association of the catecholaminergic termin als with these peptidergic categories. In both types of dually stained sections, catecholaminergic synapses were preferentially made with unlabeled dendrites. The homogeneous distribution of tyrosine hydroxylase-immunoreactive fibers in the suprachiasmatic nucleus could therefore reflect a lack of significant catecholaminergic innervation of both vasoactive intestinal peptide- and vasopressin-synthesizing neurons.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00304514
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 39
    Electronic Resource
    Electronic Resource
    Morphological study of amelogenesis in the rat lower incisor after thyro-parathyroidectomy, parathyroidectomy and thyroidectomy (1995)
    Springer
    Cell & tissue research 283 (1995), S. 151-157 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Thyro-parathyroidectomy ; Parathyroidectomy ; Enamel formation ; Light microscopy ; Electron microscopy ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. The effects of thyro-parathyroidectomy, parathyroidectomy or thyroidectomy upon enamel formation in the rat incisor were studied. One control group and four groups of surgically treated rats were used: parathyroid autotransplanted, thyroidectomized, parathyroidectomized, and thyro-parathyroidectomized. One month after surgery, the incisors were processed for light and electron microscopy. The present study revealed perturbations of the Tomes’ process morphology, of the rod pattern in the inner enamel formation, of the enamel surface, and of the mineralization after thyro-parathyroidectomy. After parathyroidectomy, only mineralization defects could be visualised. No effects were observed in enamel after thyroidectomy. A severe hypocalcemic state as seen in thyro-parathyroidectomized rats affects the enamel shape, and mineralization, and the morphology and function of secretory ameloblasts. Knowledge of the way in which the alteration of the enamel surface is produced should contribute to a better understanding of the development of tooth enamel.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410050523
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 40
    Electronic Resource
    Electronic Resource
    Cranial meninges of goldfish: age-related changes in morphology of meningeal cells and accumulation of surfactant-like multilamellar bodies (1995)
    Springer
    Cell & tissue research 281 (1995), S. 349-358 
    Details
    ISSN: 1432-0878
    Keywords: Meninges ; Cerebrospinal fluid ; Electron microscopy ; Aging ; Multilamellar bodies ; Surfactant ; Goldfish ; Carassius auratus (Teleostei)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract In the optic tectum of goldfish, the outer, middle and inner layers of the endomeninx were evident in animals ranging in age from 1 month to several years. The outer layer in young animals consisted of closely overlapping cells with intertwined processes, whereas in the older animals it contained large extracellular spaces. The intermediate layer cells were always arranged in a single continuous layer, but in young animals they overlapped extensively with one another toward their edges whereas in the oldest animals they became extremely flat and non-overlapping. The inner layer included an outer tier of cells with their bases adhering to the intermediate layer, and an inner tier of cells detached from both the intermediate layer and the basal lamina overlying the brain parenchyma. Inner layer cells contained many large vacuoles that were in continuity with the extracellular space. With age, the extracellular space and the vacuolar system expanded, and the inner layer evolved into a meshwork of attenuated cytoplasmic processes embedded in the granular extracellular matrix. Another age-related feature was the accumulation adjacent to the basal lamina of uniform disc-shaped membranous structures, resembling multilamellar bodies of lung surfactant. These “disc bodies” were apparently generated by the coalescence of vesicles formed at the surface of the inner layer cells, possibly as a by-product of protein secretion by these cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00583403
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 41
    Electronic Resource
    Electronic Resource
    Do vasoactive intestinal peptide (VIP)- and nitric oxide synthase-immunoreactive terminals synapse exclusively with VIP cell bodies in the submucous plexus of the guinea-pig ileum? (1995)
    Springer
    Cell & tissue research 281 (1995), S. 485-491 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Nitric oxide synthase ; Vasoactive intestinal peptide ; Immunohistochemistry ; Electron microscopy ; Submucous plexus ; Guinea-pig
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. In the submucous plexus of the guinea-pig ileum, previous light-microscopic studies have revealed that vasoactive intestinal peptide (VIP)-immunoreactive and nitric oxide synthase (NOS)-immunoreactive terminals are found predominantly in association with VIP-immunoreactive nerve cell bodies. In this study, double-label immunohistochemistry at the light-microscopic level demonstrated co-localization of NOS-immunoreactivity and VIP-immunoreactivity in axon terminals in submucous ganglia. About 90% of nerve fibres with NOS-immunoreactivity or VIP-immunoreactivity were immunoreactive for both antigens; only about 10% of labelled varicosities contained only NOS-immunoreactivity or VIP-immunoreactivity. The VIP/NOS varicosities were more often seen in the central parts of the ganglia, close to the VIP-immunoreactive cell bodies. Ultrastructural immunocytochemistry with antibodies to VIP was used to determine if NOS/VIP terminals synapse exclusively with VIP-immunoreactive nerve cell bodies. We examined the targets of VIP-immunoreactive boutons in two submucous ganglia from different animals. Serial ultrathin sections were taken through the ganglia after they had been processed for VIP immunocytochemistry. For each cell body, the number of VIP inputs (synapses and close contacts) was determined. The number of VIP-immunoreactive synapses received by the cell bodies of submucous neurons varied from 0–4 and the number of VIP-immunoreactive close contacts varied from 3–10. There was no significant difference between VIP-immunoreactive nerve cell bodies and non-VIP nerve cell bodies in the number of VIP-immunoreactive synapses and close contacts they received. Thus, the implication from light microscopy that NOS/VIP terminals end predominantly on VIP nerve cells was not vindicated by electron microscopy.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410050443
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 42
    Electronic Resource
    Electronic Resource
    Localization of CD44, the hyaluronate receptor, on the plasma membrane of osteocytes and osteoclasts in rat tibiae (1995)
    Springer
    Cell & tissue research 280 (1995), S. 225-233 
    Details
    ISSN: 1432-0878
    Keywords: Key words: CD44 ; adhesion molecule ; Bone ; Osteoclasts ; Osteocytes ; Immunohistochemistry ; Confocal laser scanning microscopy ; Electron microscopy ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. CD44 is a multifunctional adhesion molecule that binds to hyaluronic acid, type I collagen, and fibronectin. We have studied the immunohistochemical localization of CD44 in bone cells by confocal laser scanning microscopy and transmission electron microscopy in order to clarify its role in the cell-cell and/or cell-matrix interaction of bone cells. In round osteoblasts attached to bone surfaces, immunoreactivity is restricted to their cytoplasmic processes. On the other hand, osteocytes in bone matrices show intense immunoreactivity on their plasma membrane. Intense immunoreactivity for CD44 can be detected on the basolateral plasma membranes of osteoclasts. There is considerably less reactivity observed in the area of the plasma membrane that is in direct contact with bone. The pre-embedding electron-microscopical method has revealed that CD44 is mainly localized on the basolateral plasma membrane of osteoclasts. However, the ruffled border and clear zone show little immunoreactivity. A CD44-positive reaction can be detected on both plasma membranes in the contact region between osteoclasts and osteocytes. These findings suggest that: 1) cells of the osteoblast lineage express CD44 in accordance with their morphological changes from osteoblasts into osteocytes; 2) osteoclasts express CD44 on their basolateral plasma membrane; 3) CD44 in osteoclasts and osteocytes may play an important role in cell-cell and/or cell-matrix attachment via extracellular matrices.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00307793
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 43
    Electronic Resource
    Electronic Resource
    Ultrastructural investigation of nitric oxide synthase-immunoreactive nerves associated with coronary blood vessels of rat and guinea-pig (1995)
    Springer
    Cell & tissue research 280 (1995), S. 575-582 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Nitric oxide synthase ; Coronary vasculature ; Electron microscopy ; Immunocytochemistry ; Rat (Sprague Dawley) ; Guinea-pig (Dunkin Hartley)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. Ultrastructural investigation of nitric oxide synthase-immunoreactive nerves closely associated with blood vessels in rat and guinea-pig hearts revealed many labelled nerve fibres in the walls of the main branches of the coronary arteries, and in arterioles, capillaries and post-capillary venules. The number of nitric oxide synthase-containing nerve fibres associated with different vessels, even those of the same calibre, varied. Terminal regions of nitric oxide synthase-immunoreactive fibres were observed in the endocardium and myocardium. Nitric oxide synthase-labelled fibres displayed electron-dense immunoproduct in both varicose and intervaricose regions. Immunoreactive axonal varicosities contained both small and large synaptic vesicles. The characteristics of the nitric oxide synthase-immunoreactive nerve fibres observed in the heart and the possibility that these fibres represent the processes of intracardiac neurones and/or sensory neurones of extrinsic origin are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00318361
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 44
    Electronic Resource
    Electronic Resource
    Ultrastructural study of periodic lamellar granules in human neutrophils (1995)
    Springer
    Cell & tissue research 281 (1995), S. 69-76 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Periodic lamellar granule ; Primary granule ; Chronic myeloproliferative disorder ; Neutrophils ; Electron microscopy ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. Granules consisting of periodically arranged membranous lamellae and amorphous electron-opaque material, i.e., periodic lamellar granules, are present in human neutrophils. To date, no extensive ultrastructural studies have been carried out on these granules because of their infrequent presence in neutrophils. The bone marrow of 18 cases of chronic myeloproliferative disorders, including one case of chronic neutrophilic leukemia in which periodic lamellar granules were frequently seen in neutrophils, was investigated by electron microscopy. Periodic lamellar granules were seen in neutrophils in 12 of the 18 cases at varying frequencies. They were preferentially seen in immature neutrophils. The transverse profiles of these granules revealed concentric complete/incomplete rings or periodic parallel straight lines, i.e., various patterns of lamellar arrangement were present. Periodic lamellar granules were positive for myeloperoxidase and lysozyme at the electron-microscopic level. These results suggest that these granules represent a primary neutrophil granule subtype. However, their functional and pathologic significance remains unknown.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00307959
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 45
    Electronic Resource
    Electronic Resource
    Immunocytochemical colocalization of adhesive proteins with clathrin in human blood platelets: further evidence for coated vesicle-mediated transport of von Willebrand factor, fibrinogen and fibronectin (1995)
    Springer
    Cell & tissue research 279 (1995), S. 453-457 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Blood platelets ; Immunocytochemistry ; Electron microscopy ; Coated vesicles ; Clathrin ; Adhesive proteins ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. Coated membranes and vesicles play an important role in receptor-mediated endocytosis and intracellular trafficking in various cell types, and are also present in blood platelets. Platelets take up certain proteins from the blood plasma, such as von Willebrand factor and fibrinogen, and these substances are transferred to storage granules. The receptors for these plasma proteins on the platelet plasma membrane have been well characterized, but morphological evidence for their transport to the storage granules is not yet available. In an attempt to clarify this aspect, we employed postembedding immunocytochemistry on platelets embedded in the acrylic resin LR White. Clathrin as the major coat component of coated vesicles was localized in the cytoplasm, on the plasmic faces of α-granules and the open canalicular system, and on the plasmic face of the plasma membrane. Colocalizations of the adhesive proteins, von Willebrand factor, fibrinogen and fibronectin, with clathrin could be observed at the same typical locations as coated vesicles were seen in Araldite-embedded material. These colocalizations have not been reported to date and furnish further evidence for a coated vesicle-mediated transport of blood plasma-derived adhesive proteins from their receptors on the outer plasma membrane to the α-granules.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410050304
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 46
    Electronic Resource
    Electronic Resource
    Cranial meninges of goldfish: age-related changes in morphology of meningeal cells and accumulation of surfactant-like multilamellar bodies (1995)
    Springer
    Cell & tissue research 281 (1995), S. 349-358 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Meninges ; Cerebrospinal fluid ; Electron microscopy ; Aging ; Multilamellar bodies ; Surfactant ; Goldfish ; Carassius auratus (Teleostei)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. In the optic tectum of goldfish, the outer, middle and inner layers of the endomeninx were evident in animals ranging in age from 1 month to several years. The outer layer in young animals consisted of closely overlapping cells with intertwined processes, whereas in the older animals it contained large extracellular spaces. The intermediate layer cells were always arranged in a single continuous layer, but in young animals they overlapped extensively with one another toward their edges whereas in the oldest animals they became extremely flat and non-overlapping. The inner layer included an outer tier of cells with their bases adhering to the intermediate layer, and an inner tier of cells detached from both the intermediate layer and the basal lamina overlying the brain parenchyma. Inner layer cells contained many large vacuoles that were in continuity with the extracellular space. With age, the extracellular space and the vacuolar system expanded, and the inner layer evolved into a meshwork of attenuated cytoplasmic processes embedded in the granular extracellular matrix. Another age-related feature was the accumulation adjacent to the basal lamina of uniform disc-shaped membranous structures, resembling multilamellar bodies of lung surfactant. These ”disc bodies” were apparently generated by the coalescence of vesicles formed at the surface of the inner layer cells, possibly as a by-product of protein secretion by these cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00583403
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 47
    Electronic Resource
    Electronic Resource
    Immunogold labelling of estradiol receptor in MCF7 cells (1995)
    Springer
    Cell & tissue research 279 (1995), S. 445-452 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Estradiol receptor ; Breast cancer cells ; Cell culture ; Ultrastructure ; Electron microscopy ; Immunohistochemistry ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. The distribution of estradiol receptor in serial sections of estradiol-deprived and estradiol-stimulated MCF7 cells was studied by using mouse monoclonal antibodies reacting with different domains of the receptor and goat-antimouse IgG/6 nm gold. In the nucleus and the cytoplasm of estradiol-deprived cells, the receptor was detected by all three monoclonals (13H2, HT 65 and MA1-310). The antibodies 13H2 and MA1-310 detected receptor associated to the microfilament bundles in the cytoplasm. Higher densities of antireceptor attachment to the nuclear areas were accompanied by a reduction in the attachment to the cytoplasm after estradiol stimulation of the cells. The results confirm earlier observations on the presence of cytoplasmic estrogen receptor in estradiol-deprived cells and support the premise of an es- tradiol-induced translocation of this ligand-dependent transcription regulator.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410050303
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 48
    Electronic Resource
    Electronic Resource
    Immunogold labelling of estradiol receptor in MCF7 cells (1995)
    Springer
    Cell & tissue research 279 (1995), S. 445-452 
    Details
    ISSN: 1432-0878
    Keywords: Estradiol receptor ; Breast cancer cells ; Cell culture ; Ultrastructure ; Electron microscopy ; Immunohistochemistry ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The distribution of estradiol receptor in serial sections of estradiol-deprived and estradiol-stimulated MCF7 cells was studied by using mouse monoclonal antibodies reacting with different domains of the receptor and goat-antimouse IgG/6 nm gold. In the nucleus and the cytoplasm of estradiol-deprived cells, the receptor was detected by all three monoclonals (13H2, HT 65 and MA1-310). The antibodies 13H2 and MA1-310 detected receptor associated to the microfilament bundles in the cytoplasm. Higher densities of antireceptor attachment to the nuclear areas were accompanied by a reduction in the attachment to the cytoplasm after estradiol stimulation of the cells. The results confirm earlier observations on the presence of cytoplasmic estrogen receptor in estradiol-deprived cells and support the premise of an estradiol-induced translocation of this ligand-dependent transcription regulator.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00318156
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 49
    Electronic Resource
    Electronic Resource
    Immunocytochemical colocalization of adhesive proteins with clathrin in human blood platelets: further evidence for coated vesicle-mediated transport of von Willebrand factor, fibrinogen and fibronectin (1995)
    Springer
    Cell & tissue research 279 (1995), S. 453-457 
    Details
    ISSN: 1432-0878
    Keywords: Blood platelets ; Immunocytochemistry ; Electron microscopy ; Coated vesicles ; Clathrin ; Adhesive proteins ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Coated membranes and vesicles play an important role in receptor-mediated endocytosis and intracellular trafficking in various cell types, and are also present in blood platelets. Platelets take up certain proteins from the blood plasma, such as von Willebrand factor and fibrinogen, and these substances are transferred to storage granules. The receptors for these plasma proteins on the platelet plasma membrane have been well characterized, but morphological evidence for their transport to the storage granules is not yet available. In an attempt to clarify this aspect, we employed postembedding immunocytochemistry on platelets embedded in the acrylic resin LR White. Clathrin as the major coat component of coated vesicles was localized in the cytoplasm, on the plasmic faces of α-granules and the open canalicular system, and on the plasmic face of the plasma membrane. Colocalizations of the adhesive proteins, von Willebrand factor, fibrinogen and fibronectin, with clathrin could be observed at the same typical locations as coated vesicles were seen in Araldite-embedded material. These colocalizations have not been reported to date and furnish further evidence for a coated vesicle-mediated transport of blood plasma-derived adhesive proteins from their receptors on the outer plasma membrane to the α-granules.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00318157
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 50
    Electronic Resource
    Electronic Resource
    Investigation of the structural and functional features of splenic ellipsoids in rainbow trout (Oncorhynchus mykiss) (1995)
    Springer
    Cell & tissue research 279 (1995), S. 469-474 
    Details
    ISSN: 1432-0878
    Keywords: Ellipsoids ; Spleen ; Electron microscopy ; Fluorescent microspheres ; Oncorhynchus mykiss (Teleostei)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The ultrastructure of ellipsoids in the spleen of rainbow trout (Oncorhynchus mykiss) is described. The endothelium of terminations of arterioles bulged into the lumen, and gaps between the endothelial cells were evident. A continuous basal lamina was not present, and there were extensive interdigitations between the endothelial cells and surrounding reticular cells. The interdigitating processes were rich in microfilaments. Intravenously injected colloidal carbon, approximately 0.03 μm in diameter, was held in the reticular matrix of the ellipsoidal wall and taken up by macrophages that extended cellular processes among the reticular and endothelial cells. The intravenous injection of fluorescent polystyrene microspheres of known diameter showed that microspheres with a diameter of 0.5 or 1.0 μm were localised in the red pulp, whereas microspheres with a diameter of 0.15 μm were retained in ellipsoidal walls. Thus, the terminations of splenic arterioles in rainbow trout were found to be consistent with descriptions of ellipsoids in other vertebrates in that they possessed a speciallised cuboidal endothelium, lacked a continuous basal lamina, were surrounded by a sheath of macrophages and reticular cells, and had a sheath of macrophages and reticular cells, and had a role in the selective filtration and retention of bloodborne particles.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00318160
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 51
    Electronic Resource
    Electronic Resource
    Electron-microscopic localisation of thiol and disulphide groups by direct monomaleimido-nanogold labelling in the spermatozoa of a marsupial, the tammar wallaby (Macropus eugenii) (1995)
    Springer
    Cell & tissue research 282 (1995), S. 291-296 
    Details
    ISSN: 1432-0878
    Keywords: Spermatozoa ; Acrosome ; Thiols ; Disulphides ; Electron microscopy ; Monomaleimido nanogold ; Macropus eugenii (Marsupialia)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract This study utilised a commercially available monomaleimido-nanogold reagent to directly label cellular thiol groups (SH) of marsupial (tammar wallaby) spermatozoa before and after reduction of disulphides (S-S) with mercaptoethylamine hydrochloride (MEA). The sperm surface, mitochondrial membranes, axoneme and tail fibres were all labelled with gold particles before MEA treatment and the label intensity was increased after S-S reduction. The acrosomal membranes and matrix of spermatozoa contained no detectable SH prior to MEA treatment. However, after moderate MEA treatment (1 mg/ml) gold label was associated with the acrosomal membrane and invaginated acrosomal membrane within the acrosomal matrix. After exposure to 5 and 10 mg/ml MEA, gold particles heavily labelled the acrosomal matrix. Thus, the acrosomal membranes and matrix of tammar wallaby spermatozoa both contain S-S cross-linked structures, and this may contribute to the unusual stability of the marsupial acrosome. Under all treatment conditions the nucleus remained unlabelled. This is consistent with early studies which indicated that cysteine was absent from the nuclear protamines. The study also demonstrated that monomaleimido-nanogold can be used to resolve SH- and S-S-rich cellular structures directly, in addition to its use to label antibodies and Fab fragments for immunochemical localisation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00319119
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 52
    Electronic Resource
    Electronic Resource
    Dynamics of secretory granules in somatotrophs of rats after stimulation with growth hormone-releasing factor: a stereological analysis (1995)
    Springer
    Cell & tissue research 282 (1995), S. 493-501 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Somatotrophs ; Growth hormone ; Growth hormone-releasing factor ; Secretory granule ; Electron microscopy ; Morphometry ; Rat (Fischer 344)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. The anterior pituitary tissue of male rats injected with growth hormone-releasing factor (GRF) was either processed for stereology at the light- and electron-microscopic levels, or homogenized for growth hormone (GH) assay 2–60 min after GRF injection. Secretory granules of somatotrophs became smaller but increased in numerical density 2 min after GRF injection. Their volume density began to increase at 5 min. The frequency of exocytosis of the granules was most prominent as early as 2 min after GRF injection and reduced thereafter. GH levels in the tissue were lowest at 2–5 min, and returned to the control value by 60 min. Serum GH levels were highest at 15 min; even at 60 min, this value was higher than in the controls. These findings suggest that secretory granules in somatotrophs are stimulated to divide by GRF, resulting in a decrease in size and an increase in number. The discrepancy between the earlier formation of new secretory granules and the later restoration of intracellular GH levels implies that GRF first stimulates the synthesis of constituents of granules other than GH, and only later the synthesis of GH, and that newly formed small secretory granules contain less GH. From the clearance rate of serum GH and the frequency of granule exocytosis, it can be estimated that about a half million granules are released to maintain 1 ng/ml of serum GH in rats.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410050500
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 53
    Electronic Resource
    Electronic Resource
    Astrocytes alter their polarity in organotypic slice cultures of rat visual cortex (1994)
    Springer
    Cell & tissue research 277 (1994), S. 557-564 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Slice culture ; Cerebral cortex ; Astrocytes ; Orthogonal arrays of particles - Freeze-fracture ; Electron microscopy ; Rat (Lewis)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. The ultrastructure of astrocytes in an organotypic slice culture of the rat visual cortex was investigated using ultrathin sections and freeze-fracture replicas. After a culture period of 9–15 days, a glial scaffold formed that separated the bulk of the slice neuropil from the medium and the underlying plasma clot. However, the glial cells and processes did not build a dense barrier but allowed the outgrowth of neurites. A basal lamina covering the medium-oriented surface of the astrocytes was not found. In freeze-fracture replicas, orthogonal arrays of particles (OAP) were characteristic components of astrocytic membranes. The OAP density in membranes bordering the medium was 35±13 OAP/μm2, corresponding to 2.5% of this membrane area; the OAP density in membranes within the slice neuropil was 22±12 OAP/μm2, corresponding to 1.4% of this membrane area. Although the difference was significant, it was greatly reduced when comparing OAP densities in endfoot and non-endfoot membranes in vivo. Another mode of polarity was recognized in astrocytes of the organotypic slice culture. In membranes of astrocytes bordering upon the medium, the density of non-OAP intramembranous particles (IMP) was clearly higher (1130±136 IMP/μm2) than in membranes of astrocytes in the center of the slice (700±172 IMP/μm2). This pronounced IMP-related polarity was observed neither in vivo nor in cultured astrocytes. The present study suggests, together with data from the literature, that the distribution of astrocytic OAP across the cell surface is influenced by the existence of a basal lamina and neuronal activity, and that astrocytes possess a more remarkable plasticity of membrane structure than previously suspected.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00300229
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 54
    Electronic Resource
    Electronic Resource
    Organization of the endoplasmic reticulum in renal cell lines MDCK and LLC-PK1 (1994)
    Springer
    Cell & tissue research 277 (1994), S. 297-307 
    Details
    ISSN: 1432-0878
    Keywords: Endoplasmic reticulum ; Cellular transport ; Mitochondria ; Electron microscopy ; Contocal microscopy ; MDCK cells ; LLC-PK1 cells
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The spatial organization of the endoplasmic reticulum has been studied in two renal cell lines, MDCK and LLC-PK1, which originate from the distal and proximal portions of the mammalian nephron, respectively, and which form a polarized epithelium when they reach confluence in tissue culture. The two renal cell lines, grown to confluence on either solid or permeable supports, were investigated by fluorescence microscopy, confocal microscopy, and transmission electron microscopy. Fluorescence labeling of the endoplasmic reticulum was achieved using the cationic fluorescent dye DIOC6 (3). In order to differentiate fluorescent labeling of the endoplasmic reticulum from that of the mitochondria, cells were also labeled with rhodamine 123. For electron microscopy, the spatial organization of the endoplasmic reticulum was examined in thick sections using the long-duration osmium impregnation technique or the ferrocyanide/osmium technique. In both cell lines, the endoplasmic reticulum formed an abundant tubular network of canaliculi that frequently abutted the basolateral domain of the plasma membrane and occasionally the apical membrane. Elements of the endoplasmic reticulum were also found in close proximity to mitochondria that, as in the nephron, formed branched structures. Canaliculi appeared circular or flattened and had an inner diameter of 10–70 nm for MDCK cells and 20–90 nm for LLC-PK1 cells. Such a three-dimensional organization might facilitate the translocation of defined lipid species between the endoplasmic reticulum and the plasma membrane, and between the endoplasmic reticulum and mitochondria.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00327777
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 55
    Electronic Resource
    Electronic Resource
    Organization of the endoplasmic reticulum in renal cell lines MDCK and LLC-PK1 (1994)
    Springer
    Cell & tissue research 277 (1994), S. 297-307 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Endoplasmic reticulum ; Cellular transport ; Mitochondria ; Electron microscopy ; Confocal microscopy ; MDCK cells ; LLC-PK1 cells
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. The spatial organization of the endoplasmic reticulum has been studied in two renal cell lines, MDCK and LLC-PK1, which originate from the distal and proximal portions of the mammalian nephron, respectively, and which form a polarized epithelium when they reach confluence in tissue culture. The two renal cell lines, grown to confluence on either solid or permeable supports, were investigated by fluorescence microscopy, confocal microscopy, and transmission electron microscopy. Fluorescence labeling of the endoplasmic reticulum was achieved using the cationic fluorescent dye DIOC6 (3). In order to differentiate fluorescent labeling of the endoplasmic reticulum from that of the mitochondria, cells were also labeled with rhodamine 123. For electron microscopy, the spatial organization of the endoplasmic reticulum was examined in thick sections using the long-duration osmium impregnation technique or the ferrocyanide/osmium technique. In both cell lines, the endoplasmic reticulum formed an abundant tubular network of canaliculi that frequently abutted the basolateral domain of the plasma membrane and occasionally the apical membrane. Elements of the endoplasmic reticulum were also found in close proximity to mitochondria that, as in the nephron, formed branched structures. Canaliculi appeared circular or flattened and had an inner diameter of 10–70 nm for MDCK cells and 20–90 nm for LLC-PK1 cells. Such a three-dimensional organization might facilitate the translocation of defined lipid species between the endoplasmic reticulum and the plasma membrane, and between the endoplasmic reticulum and mitochondria.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410050156
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 56
    Electronic Resource
    Electronic Resource
    Progressive reorganization of the myenteric plexus during one year following reanastomosis of the ileum of the guinea pig (1994)
    Springer
    Cell & tissue research 277 (1994), S. 259-272 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Ileum ; Transection ; Reanastomosis ; Myenteric plexus ; NADH diaphorase histochemistry ; Neuron-specific enolase ; Electron microscopy ; Guinea pig
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. The enteric nervous system appears to play a pivotal role in the functional recovery of the gastrointestinal tract after partial resection and reanastomosis, but the structural changes following surgery are not fully understood. The present study was designed to clarify the processes of myenteric plexus regeneration up to one year after transection and reanastomosis of the ileum of the guinea pig. The following techniques were used: nicotinamide adenine dinucleotide (NADH) diaphorase histochemistry, immunostaining of neuron-specific enolase (NSE) in whole-mount preparations, and transmission electron microscopy. Two months after transection and reanastomosis, myenteric ganglion cells with NADH diaphorase reactions were scarce in the center of the lesion, and were less numerous in adjacent areas (3 mm in width) than in the control ileum. In the areas adjacent to the lesion, a few large extraganglionic neurons that did not completely compensate for the loss of ganglion neurons were observed. The remaining ileum showed no changes in NADH diaphorase staining pattern at this stage. Two to 12 months after transection and reanastomosis, ectopic large neurons gradually increased in number not only in the areas adjacent to the lesion but also in part of the remaining ileum, up to 10 cm from the lesion. Concomitantly, large ganglion neurons decreased in number in these areas. In other ileal regions (more than 10 cm distant from the site of transection), no obvious changes in NADH diaphorase staining were noted throughout the observation period. The outgrowth of NSE-containing nerve fibers from the severed stumps was seen two weeks after transection. Six weeks later, numerous bundles of fine nerve fibers with NSE were shown to interconnect the oral and anal cut ends of the myenteric plexus, but they exhibited no subsequent alterations. Transmission electron microscopy revealed that regenerating nerve fiber bundles appeared initially among irregularly arranged smooth muscle cells eight weeks after the operation, as expected from light-microscopic observations. These findings suggest that myenteric ganglion cell bodies, unlike myenteric nerve fibers, require a longer term of reconstruction than previously believed after transection and reanastomosis of the ileum of the guinea pig.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410050153
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 57
    Electronic Resource
    Electronic Resource
    Progressive reorganization of the myenteric plexus during one year following reanastomosis of the ileum of the guinea pig (1994)
    Springer
    Cell & tissue research 277 (1994), S. 259-272 
    Details
    ISSN: 1432-0878
    Keywords: Ileum ; Transection ; Reanastomosis ; Myenteric plexus ; NADH diaphorase histochemistry ; Neuron-specific enolase ; Electron microscopy ; Guinea pig
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The enteric nervous system appears to play a pivotal role in the functional recovery of the gastrointestinal tract after partial resection and reanastomosis, but the structural changes following surgery are not fully understood. The present study was designed to clarify the processes of myenteric plexus regeneration up to one year after transection and reanastomosis of the ileum of the guinea pig. The following techniques were used: nicotinamide adenine dinucleotide (NADH) diaphorase histochemistry, immunostaining of neuron-specific enolase (NSE) in whole-mount preparations, and transmission electron microscopy. Two months after transection and reanastomosis, myenteric ganglion cells with NADH diaphorase reactions were scarce in the center of the lesion, and were less numerous in adjacent areas (3 mm in width) than in the control ileum. In the areas adjacent to the lesion, a few large extraganglionic neurons that did not completely compensate for the loss of ganglion neurons were observed. The remaining ileum showed no changes in NADH diaphorase staining pattern at this stage. Two to 12 months after transection and reanastomosis, ectopic large neurons gradually increased in number not only in the areas adjacent to the lesion but also in part of the remaining ileum, up to 10 cm from the lesion. Concomitantly, large ganglion neurons decreased in number in these areas. In other ileal regions (more than 10 cm distant from the site of transection), no obvious changes in NADH diaphorase staining were noted throughout the observation period. The outgrowth of NSE-containing nerve fibers from the severed stumps was seen two weeks after transection. Six weeks later, numerous bundles of fine nerve fibers with NSE were shown to interconnect the oral and anal cut ends of the myenteric plexus, but they exhibited no subsequent alterations. Transmission electron microscopy revealed that regenerating nerve fiber bundles appeared initially among irregularly arranged smooth muscle cells eight weeks after the operation, as expected from light-microscopic observations. These findings suggest that myenteric ganglion cell bodies, unlike myenteric nerve fibers, require a longer term of reconstruction than previously believed after transection and reanastomosis of the ileum of the guinea pig.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00327773
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 58
    Electronic Resource
    Electronic Resource
    Astrocytes alter their polarity in organotypic slice cultures of rat visual cortex (1994)
    Springer
    Cell & tissue research 277 (1994), S. 557-564 
    Details
    ISSN: 1432-0878
    Keywords: Slice culture ; Cerebral cortex ; Astrocytes ; Orthogonal arrays of particles ; Freeze-fracture ; Electron microscopy ; Rat (Lewis)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The ultrastructure of astrocytes in an organotypic slice culture of the rat visual cortex was investigated using ultrathin sections and freeze-fracture replicas. After a culture period of 9–15 days, a glial scaffold formed that separated the bulk of the slice neuropil from the medium and the underlying plasma clot. However, the glial cells and processes did not build a dense barrier but allowed the outgrowth of neurites. A basal lamina covering the medium-oriented surface of the astrocytes was not found. In freeze-fracture replicas, orthogonal arrays of particles (OAP) were characteristic components of astrocytic membranes. The OAP density in membranes bordering the medium was 35±13 OAP/μm2, corresponding to 2.5% of this membrane area; the OAP density in membranes within the slice neuropil was 22±12 OAP/μ2, corresponding to 1.4% of this membrane area. Although the difference was significant, it was greatly reduced when comparing OAP densities in endfoot and non-endfoot membranes in vivo. Another mode of polarity was recognized in astrocytes of the organotypic slice culture. In membranes of astrocytes bordering upon the medium, the density of non-OAP intramembranous particles (IMP) was clearly higher (1130±136 IMP/ μm2) than in membranes of astrocytes in the center of the slice (700±172 IMP/μm2). This pronounced IMP-related polarity was observed neither in vivo nor in cultured astrocytes. The present study suggests, together with data from the literature, that the distribution of astrocytic OAP across the cell surface is influenced by the existence of a basal lamina and neuronal activity, and that astrocytes possess a more remarkable plasticity of membrane structure than previously suspected.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00300229
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 59
    Electronic Resource
    Electronic Resource
    Fine structure and lectin histochemistry of the apical surface of the free neuromast of Lampetra japonica (1994)
    Springer
    Cell & tissue research 276 (1994), S. 245-252 
    Details
    ISSN: 1432-0878
    Keywords: Neuromast ; Hair cells ; Surface coat ; Electron microscopy ; Lectin histochemistry ; Lampetra japonica (Cyclostomata)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The surface coat, ciliary process, and microvilli of the lamprey neuromast were examined with electron microscopy after tannic acid prefixation and lectin histochemistry. The neuromast was found to exist in the form of a dermal mound with a furrow in the middle. On the bottom of the furrow, the hair cell was characterized by a kinocilium and 15–20 stereocilia, arranged along the longitudinal axis of the furrow. Spanning structures were demonstrated between the kinocilium and stereocilia as well as between stereocilia. The surface coat, enhanced by tannic acid prefixation, was particularly rich over the surface of the supporting cell; by contrast, it was thin over the hair cell. Some lectins (PNA, GS-I, SBA, WGA) showed affinity to the surface coat of the supporting cell as well as the hair cell, and the others (RCA-I, MPA, ConA) showed affinity only to the supporting cell. These differences in the structure and affinities of the surface coat suggest an extracellular milieu highly specialized for the hair cell in this particular form of the mechanoreceptor.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00306110
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 60
    Electronic Resource
    Electronic Resource
    Zona glomerulosa of the adrenal gland in a transgenic strain of rat: a morphologic and functional study (1994)
    Springer
    Cell & tissue research 278 (1994), S. 21-28 
    Details
    ISSN: 1432-0878
    Keywords: Adrenal cortex ; Renin-angiotensin system ; Steroidogenesis ; Electron microscopy ; Morphometry ; Rat, transgenic (mRen2) 27
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Transgenic rats for the murine Ren-2 gene display high blood pressure, low circulating levels of angiotensin II, and high renin content in the adrenal glands. Moreover, transgenic rats possess and increased aldosterone secretion (maximal from 6 to 18 weeks of age), paralleling the development of hypertension. To investigate further the cytophysiology of the adrenal glands of this strain of rats, we performed a combined morphometric and functional study of the zona glomerulosa of 10-week-old female transgenic rats. Morphometry did not reveal notable differences between zona glomerulosa cells of transgenic and age- and sex-matched Sprague-Dawley rats, with the exception of a marked accumulation of lipid droplets, in which cholesterol and cholesterol esters are stored. The volume of the lipid-droplet compartment underwent a significant decrease when transgenic rats were previously injected with angiotensin II or ACTH. Dispersed zona glomerulosa cells of transgenic rats showed a significantly higher basal aldosterone secretion, but their response to angiotensin II and ACTH was similar to that of Sprague-Dawley animals. Angiotensin II-receptor number and affinity were not dissimilar in zona glomerulosa cells of transgenic and Sprague-Dawley rats. These data suggest that the sustained stimulation of the adrenal renin-angiotensin system in transgenic animals causes an increase in the accumulation in zona glomerulosa cells of cholesterol available for steroidogenesis, as indicated by the expanded volume of the lipid-droplet compartment and the elevated basal steroidogenesis. However, the basal hyperfunction of the zona glomerulosa in transgenic animals does not appear to be coupled with an enhanced responsivity to its main secretagogues, at least in terms of aldosterone secretion.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00305774
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 61
    Electronic Resource
    Electronic Resource
    Morphological studies by light and electron microscopy of pancreatic acinar cells under the effect of Tityus serrulatus venom (1994)
    Springer
    Cell & tissue research 278 (1994), S. 255-264 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Scorpion venom ; Exocrine pancreas ; Secretagogue ; Electron microscopy ; Pancreatitis ; cis-Golgi aggregates
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. We studied in vivo and in vitro morphological aspects of pancreatic acinar cells after treatment with Tityus serrulatus venom (TSV). After three hours in an in vitro system, positive secretagogue effects of the venom were identifiable both at the light-microscopic (LM) and the electron-microscopic (EM) levels. At 1 μg/ml TSV, maximal secretion (as measured in a concomitant radiolabeling dose-response experiment) of exocrine proteins at 58% was manifest as a discharge of most zymogen granules (ZG) and consequent appearance of secretory material in acinar lumina. At the supramaximal dose of 10 μg/ml TSV, exocytotic images were often observed also with secretory contents previously discharged. The lowest dose of venom at 0.01 μg/ml caused no stimulation of zymogen discharge above resting secretion levels; however, morphological changes were observed. At high doses of TSV, both in vivo and in vitro, large aggregates associated with the cis-Golgi develop between this region and the endoplasmic reticulum (ER). Since Tityus venoms have been associated with causation of pancreatitis, we were interested in comparisons of our experimental tissue with parameters attributed to development of the disease. Our studies have demonstrated considerable evidence that large intracellular vacuoles, discharged ZG, effaced acinar lumina with disappearance of microvilli and other manifestations of possible early events in pancreatitis are indeed frequently observed both in pancreatic lobules in vitro and in whole pancreas in vivo when exposed to TSV.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00414168
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 62
    Electronic Resource
    Electronic Resource
    Zona glomerulosa of the adrenal gland in a transgenic strain of rat: a morphologic and functional study (1994)
    Springer
    Cell & tissue research 278 (1994), S. 21-28 
    Details
    ISSN: 1432-0878
    Keywords: Key words: Adrenal cortex ; Renin-angiotensin system ; Steroidogenesis ; Electron microscopy ; Morphometry ; Rat ; transgenic (mRen2) 27
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. Transgenic rats for the murine Ren-2 gene display high blood pressure, low circulating levels of angiotensin II, and high renin content in the adrenal glands. Moreover, transgenic rats possess an increased aldosterone secretion (maximal from 6 to 18 weeks of age), paralleling the development of hypertension. To investigate further the cytophysiology of the adrenal glands of this strain of rats, we performed a combined morphometric and functional study of the zona glomerulosa of 10-week-old female transgenic rats. Morphometry did not reveal notable differences between zona glomerulosa cells of transgenic and age- and sex-matched Sprague-Dawley rats, with the exception of a marked accumulation of lipid droplets, in which cholesterol and cholesterol esters are stored. The volume of the lipid-droplet compartment underwent a significant decrease when transgenic rats were previously injected with angiotensin II or ACTH. Dispersed zona glomerulosa cells of transgenic rats showed a significantly higher basal aldosterone secretion, but their response to angiotensin II and ACTH was similar to that of Sprague-Dawley animals. Angiotensin II-receptor number and affinity were not dissimilar in zona glomerulosa cells of transgenic and Sprague-Dawley rats. These data suggest that the sustained stimulation of the adrenal renin-angiotensin system in transgenic animals causes an increase in the accumulation in zona glomerulosa cells of cholesterol available for steroidogenesis, as indicated by the expanded volume of the lipid-droplet compartment and the elevated basal steroidogenesis. However, the basal hyperfunction of the zona glomerulosa in transgenic animals does not appear to be coupled with an enhanced responsivity to its main secretagogues, at least in terms of aldosterone secretion.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00305774
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 63
    Electronic Resource
    Electronic Resource
    Immunocytochemical localization of a growth-associated protein (GAP-43) in rat adrenal gland (1994)
    Springer
    Cell & tissue research 275 (1994), S. 555-566 
    Details
    ISSN: 1432-0878
    Keywords: Adrenal ; Autonomic nervous system ; Schwann cells ; Tyrosine hydroxylase ; GAP-43 ; Electron microscopy ; Immunohistochemistry ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract We have localized at light and electron-microscopic level the growth-associated protein GAP-43 in adrenal gland using single and double labelling immunocytochemistry. Clusters of GAP-43-immunofluorescent chromaffin cells and many immunofluorescent fibres were observed in the medulla. GAP-43-immunoreactive fibres also formed a plexus under the capsule, crossed the cortex and ramified in the zona reticulata. Double labelled sections showed the coexpression of GAP-43 with a subpopulation of tyrosine hydroxylase-and of dopamine-β-hydroxylase-immunoreactive chromaffin cells. Dual colour immunofluorescence for GAP-43 and calcitonin gene-related peptide (CGRP) revealed that some of the GAP-43-immunoreactive fibres also express CGRP. Pre-embedding electron microscopy showed GAP-43 immunoreactivity associated with the plasma membranes and cytoplasm of noradrenaline-producing chromaffin cells, and with processes of nonmyelin-forming Schwann cells. Immunoreactive unmyelinated axons and terminals were also observed. The immunostained terminals made symmetrical synaptic contacts with chromaffin cells. Immunoreactive unmyelinated fibres and small terminals were present in the cortex. Our results show that GAP-43 is expressed in noradrenergic chromaffin cells and in various types of nerve fibres that innervate the adrenal. Likely origins for these fibres include preganglionic sympathetic fibres which innervate chromaffin cells, postganglionic sympathetic fibres in the cortex, and CGRP containing sensory fibres.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00318824
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 64
    Electronic Resource
    Electronic Resource
    Light- and electron-microscopic study of electrophysiologically characterized neurons in the mediolateral part of the lateral septum of the guinea-pig (1994)
    Springer
    Cell & tissue research 275 (1994), S. 543-553 
    Details
    ISSN: 1432-0878
    Keywords: Lateral septum ; Intracellular injections ; Electron microscopy ; Somatie spines ; Guinea-pig
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract In slices of guinea-pig brains, 36 neurons located in the mediolateral part of the lateral septum were stained intracellularly with horseradish peroxidase (n=28) or biocytin (n=8) after electrophysiological characterization. These neurons belonged to class A neurons (n=23), which generated pronounced Ca++-dependent high-threshold spikes in control medium, or to class C neurons (n=9), which were recognized by the occurrence of small-amplitude sodic spikes followed by slower larger calcic spikes. The present results demonstrate that, despite the variety of individual cell types, the major morphological population (30/36 cells) was composed of a homogeneous class of large-sized neurons that displayed thick primary dendrites and abundant dendritic appendages. The remaining 6 cells were small-sized, poorly-spiny neurons. Somatic spines were observed on 5 out of the 30 large cells and on one out of the six smaller cells. Labeled axons were mainly oriented to the anterior commissure. The axons of nine cells richly collateralized near the perikaryon. Ultrastructural examination of 3 horseradish peroxidase-injected cells showed indented nuclei, classic organelles and somatic spines. Terminal boutons established symmetric synapses with the injected cells. These results describe the morphological features of electrophysiologically identified neurons and indicate that class A and class C neurons are distributed among morphological populations differing in perikaryal size. This suggests that the different electrical properties of class A and class C neurons reflect recordings from different parts of the neuron rather than from neurons of different types. Furthermore, the present findings demonstrate that, in the guinea-pig, electrical and morphological characteristics of somatospiny neurons are comparable with those of non-somatospiny neurons. Somatospiny neurons have a recognized integrative role in the hippocampo-septo-hypothalamic complex.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00318823
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 65
    Electronic Resource
    Electronic Resource
    Quantitative analysis of rod-cored vesicles and dense granules of large granular lymphocytes in the liver, spleen, and peripheral blood of rats (1994)
    Springer
    Cell & tissue research 276 (1994), S. 187-195 
    Details
    ISSN: 1432-0878
    Keywords: Rod-coredvesicles ; Granules ; Lymphocytes ; Liver ; Electron microscopy ; Rat (Fischer F344/NCR)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Large granular lymphocytes (LGL) comprise a natural defense system in the liver and exert an inhibitory effect on tumor cell metastasis. In order to demonstrate the maturation of LGL in the liver from the morphological aspect, we evaluated electron-microscopically the frequency of 0.2 μm vesicles (rod-cored and “empty” vesicles) and dense granules in LGL from the liver, spleen, and peripheral blood of the rat. Both of these cell organelles are characteristic to LGL and may relate to natural killer-mediated cytolysis. On the average, there were 12.7 of the 0.2 μm vesicles and 4.3 rod-cored vesicles (RCV) per cell section in the liver, 6.6 0.2 μm vesicles and 1.6 RCV in the spleen, and 8.6 0.2 μm vesicles and 0.9 RCV in the peripheral blood. The number of 0.2 μm vesicles per cell section ranged from 0 to 19 with the exception of a few higher instances. Therefore, LGL were divided into vesicle-rich(〉9 0.2 μm vesicles per cell section) and vesicle-poor (〈8 per cell section) populations. Hepatic LGL consisted mainly of a vesicle-rich population while splenic LGL consisted mainly of a vesicle-poor population, and peripheral blood contained equal proportions of both populations. In addition to diversity with regard to the number of 0.2 μm vesicles, LGL obtained from various organs also displayed heterogeneity in the number and size of dense granules. Since the number of dense granules per cell section usually ranged from 1 to 13, LGL were diveded into 2 populations, i.e., LGL with many (〉7 per cell section) granules and those with a few(〈6 per cell section) granules. Specifically, splenic LGL had a few small (average diameter, less than 400 nm) dense granules, while sections of LGL from the liver and peripheral blood displayed many small dense granules and a few large (〉400 nm) ones, respectively, in addition to the populations seen in the spleen. Thus, the present study has demonstrateda difference in the distribution of 0.2 μm vesicles in LGL based on the tissue of origin. The present study has revealed the difference in the distribution of 0.2 μm vesicles of LGL by tissue and indicated that immature LGL are predominant in the spleen, while hepatic LGL are generally more mature as defined by the number of vesicles. These data suggest that the microenvironment of the liver may contribute to the increased expression of these vesicles in LGL.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00354799
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 66
    Electronic Resource
    Electronic Resource
    Localization of GABAA receptors in the rabbit retina (1994)
    Springer
    Cell & tissue research 276 (1994), S. 295-307 
    Details
    ISSN: 1432-0878
    Keywords: GABAA receptors ; Light microscopy ; Electron microscopy ; α1 subunit ; β2/3 subunit ; γ2 subunit ; Immunocytochemistry ; Rabbit (New Zealand)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The distribution of gamma-aminobutyric acidA (GABAA) receptors in the rabbit retina is investigated and compared with the distribution of GABAergic neurons using immunocytochemical methods. Antibodies against the α1, β2/3, and γ2 subunits of the GABAA receptor label subpopulations of bipolar, amacrine and ganglion cells. Double labeling experiments show that the γ2 subunit is colocalized with the α1 and the β2/3 subunits in bipolar, amacrine and ganglion cells. Electron microscopy reveals that in the outer plexiform layer, GABAA receptor immunoreactivity is present on dendrites of cone bipolar cells adjacent to the cone pedicles. Bipolar cell dendrites are also receptor-positive at synapses from interplexiform cells. Some receptor immunoreactivity is found intracellularly in processes of horizontal cells. In the inner plexiform layer, GABAA receptor immunoreactivity is present on both rod bipolar and cone bipolar axon terminals at putative GABAergic input sites. Amacrine and ganglion cell processes in sublamina a and b are also labeled.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00306115
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 67
    Electronic Resource
    Electronic Resource
    Negatively-stained polysomes on rough microsome vesicles viewed by electron microscopy: further evidence regarding the orientation of attached ribosomes (1994)
    Springer
    Cell & tissue research 276 (1994), S. 439-444 
    Details
    ISSN: 1432-0878
    Keywords: Polysomes ; Ribosomes ; Subunits ; Liver ; Electron microscopy ; Negative stain ; Rat (Sprague-Dawley)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Rough microsomes, derived from rough endoplasmic reticulum of rat liver, were studied by electron microscopy after negative staining, to seek further information about the orientation of ribosomal small and large subunits in bound polysomes. Rough microsomal vesicles were fixed with 2% formaldehyde, centrifuged onto electron-microscopic grid membranes, and were then negatively-stained with 2% phosphotungstic acid. In these preparations, viewed with the electron microscope, flattened rough microsomal vesicles with bound polysomes were sometimes discernible, and the individual ribosomes in the polysomes occasionally showed small and large subunits. The small subunits were uniformly oriented toward the inside of the polysomal curve. The large and small subunits appeared to be alongside one another on the membrane, consistent with the orientation that has been described by Unwin and his co-workers. The boundary between the small and large subunits occurred at approximately the same level in the ribosome where inter-ribosomal strands have been described previously in surface views of bound polysomes in positively-stained electron-microscopic tissue sections. This further confirms the identity of the strands as messenger RNA.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00343942
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 68
    Electronic Resource
    Electronic Resource
    Morphological studies by light and electron microscopy of pancreatic acinar cells under the effect of Tityus serrulatus venom (1994)
    Springer
    Cell & tissue research 278 (1994), S. 255-264 
    Details
    ISSN: 1432-0878
    Keywords: Scorpion venom ; Exocrine pancreas ; Secretagogue ; Electron microscopy ; Pancreatitis ; cis-Golgi aggregates
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract We studied in vivo and in vitro morphological aspects of pancreatic acinar cells after treatment with Tityus serrulatus venom (TSV). After three hours in an in vitro system, positive secretagogue effects of the venom were identifiable both at the light-microscopic (LM) and the electron-microscopic (EM) levels. At 1 μg/ml TSV, maximal secretion (as measured in a concomitant radiolabeling dose-response experiment) of exocrine proteins at 58% was manifest as a discharge of most zymogen granules (ZG) and consequent appearance of secretory material in acinar lumina. At the supramaximal dose of 10 μg/ml TSV, exocytotic images were often observed also with secretory contents previously discharged. The lowest dose of venom at 0.01 μg/ml caused no stimulation of zymogen discharge above resting secretion levels; however, morphological changes were observed. At high doses of TSV, both in vivo and in vitro, large aggregates associated with the cis-Golgi develop between this region and the endoplasmic reticulum (ER). Since Tityus venoms have been associated with causation of pancreatitis, we were interested in comparisons of our experimental tissue with parameters attributed to development of the disease. Our studies have demonstrated considerable evidence that large intracellular vacuoles, discharged ZG, effaced acinar lumina with disappearance of microvilli and other manifestations of possible early events in pancreatitis are indeed frequently observed both in pancreatic lobules in vitro and in whole pancreas in vivo when exposed to TSV.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00414168
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 69
    Electronic Resource
    Electronic Resource
    Effects of aflatoxin B1 on in vitro cultures ofNicotiana tabacum var. Samsun (1994)
    Springer
    Mycopathologia 125 (1994), S. 93-105 
    Details
    ISSN: 1573-0832
    Keywords: Aflatoxin B1 ; Callus ; Differentiation ; Electron microscopy ; Organogenesis ; Tobacco
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Calli ofNicotiana tabacum (tobacco) were treated with two dose ranges of aflatoxin B1 (0.1–2.0 µg ml−1 - low does; 5–25 µg ml−1 aflatoxin B1). The ability of calli to recover following 3 weeks of toxin exposure was also investigated. The I50 (50% inhibition) value for fresh mass accumulation was approximately 2 µg ml−1 AFB1. Fresh mass accumulation was significantly lower than the control value from 0.5 µg ml−1 AFB1. Following 3 weeks growth without a toxin source, the growth of calli up to and including 10 µg ml−1 AFB1, was significantly greater than control calli, indicating reversibility of the toxic effects. With increasing toxin concentration, chlorophyll content of callus was inhibited from 0.5 µg ml−1. Transfer to a toxin-free medium resulted in a degree of recovery (up to 0.5 µg ml−1). In the dose range 5–25 µg ml−1, the levels of chlorophyll were drastically reduced, with no recovery following AFB1 removal. Electron microscopy revealed a disruption of chloroplast structure as an early deteriorative event in AFB1 exposure of callus cells. Protein levels were less sensitive, with inhibition manifested only in the high dose range. Shoot development occurred at all concentrations, but was significantly inhibited from 5 µg ml−1 AFB1. Recovery following toxin removal was minimal at these higher AFB1 concentrations. The number of necrotic calli increased progressively from 5 µg ml−1 as toxin levels increased.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01371098
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 70
    Electronic Resource
    Electronic Resource
    Two bacteria causing farmer's lung: Fine structure ofThermoactinomyces vulgaris andSaccharopolyspora rectivirgula (1993)
    Springer
    Mycopathologia 121 (1993), S. 143-147 
    Details
    ISSN: 1573-0832
    Keywords: Electron microscopy ; Farmer's lung ; Saccharopolyspora rectivirgula ; Thermoactinomyces vulgaris
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The fine structure ofThermoactinomyces vulgaris andSaccharopolyspora rectivirgula is described by transmission electron microscopy. These two bacteria are the most common microbes causing farmer's lung. The fine structure of hyphae, germination of endospores and the details of conidial wall layers ofT. vulgaris, as well as the fine structure of septate hypha and globose, polygonal conidia ofS. rectivirgula are described. The conidial wall ofT. vulgaris consisted of an inner multilayered spore coat, intermediate spore coat and outer spore coat. The findings are important for the investigations to find fragments of these bacteria in the lungs of exposed patients and experimental animals.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01104069
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 71
    Electronic Resource
    Electronic Resource
    Electron microscopy of calcification during high-density suspension culture of chondrocytes (1993)
    Springer
    Calcified tissue international 53 (1993), S. 127-134 
    Details
    ISSN: 1432-0827
    Keywords: Chondrocytes ; High-density suspension culture ; Electron microscopy ; Matrix vesicle ; Apatite formation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Chondrocyte cultures grown in centrifuge tubes with intermittent centrifugation differentiate into hypertrophic chondrocytes and form calcification. We examined chondrocytes cultured in this system electron microscopically. Rat growth-plate chondrocytes were seeded in a plastic centrifuge tube and cultured in the presence of Eagle's minimum essential medium supplemented with 10% fetal bovine serum and 50 μg of ascorbic acid per ml. Specimens were examined by using electron microscopy and selected-area electron-diffraction techniques. In the early stage of culture, a few chondrocytes were scattered and extracellular matrices were not observed. In the middle stage of the cultures, the chondrocytes resembled proliferative cells. Matrix vesicles appeared to be budding from the cell surfaces of chondrocytes and were observed sparsely in the extracellular matrices, which were well formed around the chondrocytes. Matrix vesicles increased substantially during the following cultures. In the mature stage of the cultures, crystal formation related to matrix vesicles was observed. In the 33-day cultures, several masses of calcified matrix were formed and it was confirmed to be apatite by selected-area electron diffraction analysis. The chondrocytes appeared hypertrophic during this same stage. The 56-day culture was similar to the 33-day culture. It was concluded that this culture system provides an extracellular-matrix mineralization which is produced by chondrocytes per se.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01321891
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 72
    Electronic Resource
    Electronic Resource
    Ultrastructure of the taste disc in the red-bellied toad Bombina orientalis (Discoglossidae, Salientia) (1993)
    Springer
    Cell & tissue research 272 (1993), S. 59-70 
    Details
    ISSN: 1432-0878
    Keywords: Sensory cells ; Taste organ ; Electron microscopy ; Bombina orientalis, Rana pipiens (Anura)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The taste disc of the red-bellied toad Bombina orientalis (Discoglossidae) has been investigated by light and electron microscopy and compared with that of Rana pipiens (Ranidae). Unlike the frog, B. orientalis possesses a disc-shaped tongue that cannot be ejected for capture of prey. The taste discs are located on the top of fungiform papillae. They are smaller than those in Ranidae, and are not surrounded by a ring of ciliated cells. Ultrastructurally, five types of cells can be identified (mucus cells, wing cells, sensory cells, and both Merkel cell-like basal cells and undifferentiated basal cells). Mucus cells are the main secretory cells of the taste disc and occupy most of the surface area. Their basal processes do not synapse on nerve fibers. Wing cells have sheet-like apical processes and envelop the mucus cells. They contain lysosomes and multivesicular bodies. Two types of sensory cells reach the surface of the taste disc; apically, they are distinguished by either a brush-like arrangement of microvilli or a rod-like protrusion. They are invaginated into lateral folds of mucus cells and wing cells. In contrast to the situation in R. pipiens, sensory cells of B. orientalis do not contain dark secretory granules in the perinuclear region. Synaptic connections occur between sensory cells (presynaptic sites) and nerve fibers. Merkel cell-like basal cells do not synapse onto sensory cells, but synapse-like connections exist between Merkel cell-like basal cells (presynaptic site) and nerve fibers.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00323571
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 73
    Electronic Resource
    Electronic Resource
    Neural structures in the receptive field of pleural ganglion mechanosensory neurons of Aplysia californica (1993)
    Springer
    Cell & tissue research 273 (1993), S. 487-497 
    Details
    ISSN: 1432-0878
    Keywords: Neurons ; Immunofluorescence ; Tubulin ; Electron microscopy ; Chemoreceptors ; Mechanoreceptors ; Aplysia californica (Mollusca)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The peripheral processes of the mechanoafferents that, when stimulated, initiate the much-studied tail withdrawal reflex of Aplysia californica have not been characterized. We show that immunofluorescence staining for class III β-tubulin highlights neurons and reveals nerve tracts and fine neuronal processes in Aplysia tissue. Coupled with transmission and scanning electron microscopy, class III β-tubulin immunofluorescence is consistent with the possibility that mechanoafferents in the receptive field of pleural ganglion mechanosensory neurons penetrate the tail epidermis and terminate as ciliated endings. This view is reinforced by comparisons among neuronal processes in several mechanosensory epidermal regions and in a chemosensory epidermis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00333703
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 74
    Electronic Resource
    Electronic Resource
    Isolated brush cells of the rat stomach retain their structural polarity (1993)
    Springer
    Cell & tissue research 271 (1993), S. 47-57 
    Details
    ISSN: 1432-0878
    Keywords: Brush cells ; Cell isolation ; Stomach ; Polarity ; Light microscopy ; Electron microscopy ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The brush cells (BC) are highly polarized elements occurring in epithelia of endodermal origin. They have a preferential topographical distribution in the organs in which they reside. In the stomach of the rat, BC prevail near the transitional zone separating the forestomach from the glandular stomach. Thus, a method was developed to isolate and recover BC from this organ with the aim of investigating the changes they may undergo after dissociation. Strips of the rat stomach were severed from the very proximal border of the glandular region and incubated in Hanks' balanced salt solution containing pronase. After sedimentation of the dissociated cells (crude sediment containing all stomach epithelial cell types) two successive cell fractions were prepared on preformed Percoll gradient in an attempt to enrich BC in a defined layer. BC were recovered in a fraction at a density close to 1.03 g/ml where they represented about 2% of all cells. The isolated BC changed their form from columnar to pear-shaped; however, they maintained their structural polarity over 2 h as demonstrated by light microscopy, transmission-and scanning-electron microscopy. The fine structure of BC was always satisfactorily preserved. Maintenance of the structural polarity of isolated BC is contrary to the general rule according to which all conventional epithelial cells examined to date lose their polarity after isolation. This result is discussed in relation to morphological findings in isolated sensory cells (hair cells, photoreceptor cells) leading to the suggestion that BC are more similar to these than to conventional epithelial cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00297540
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 75
    Electronic Resource
    Electronic Resource
    Cathodoluminescence-emitting lipid droplets in rat testis: a study by analytical color fluorescence electron microscopy (1993)
    Springer
    Cell & tissue research 271 (1993), S. 217-225 
    Details
    ISSN: 1432-0878
    Keywords: Testis ; Electron microscopy ; Cathodoluminescence ; Lipid droplets ; Cholesterol esters ; Vitamin A esters ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Cathodoluminescence (CL) from lipid droplets (LDs) in the rat testis was examined by analytical color fluorescence electron microscopy. The results show that (1) the Cl at wavelengths of 320 nm (CL320) and 450 nm (CL450) is derived from cholesterol esters and a mixture of lipids including vitamin A esters, respectively; (2) CL320 in the LDs of Leydig cells sharply decreases on postnatal day 21, while CL320 and CL450 in the LDs of Sertoli cells begin to be detectable; (3) the CL450-emitting LDs in seminiferous tubules, whose distributional patterns display cyclic changes during the spermatogenic cycle, are involved in spermatogenesis; and (4) the intensity of CL as well as the distributional patterns of CL-emitting LDs in testicular cells change after hypophysectomy, vitamin-A deficiency, and treatment with ethylene dimethane sulfonate and testosterone propionate. This study demonstrates that analytical color fluorescence electron microscopy is a useful tool for in-vivo observation of some specific compounds which cannot be visualized by other methods.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00318608
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 76
    Electronic Resource
    Electronic Resource
    Modulation of galanin and neuromedin U-like immunoreactivity in rat corticotropes after alteration of endocrine status (1993)
    Springer
    Cell & tissue research 272 (1993), S. 137-146 
    Details
    ISSN: 1432-0878
    Keywords: Pituitary ; Galanin ; Neuromedin-U ; Corticotropes ; Immunocytochemistry ; Electron microscopy ; Plasticity ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The localization of galanin in rat lactotropes and human corticotropes is well established. Neuromedin U immunoreactivity is present in rat corticotropes but radioimmunoassay of thyroid-manipulated rat pituitaries has also linked it to the thyroid axis. We found galanin immunoreactivity in some rat corticotropes, so we have re-examined rat anterior pituitary galanin- and neuromedin U-like immunoreactivity by use of immunocytochemistry and electron microscopy in rats in the normal state and after estrogen administration or adrenalectomy. In normal rats galanin immunoreactivity was present in a few corticotropes and lactotropes, females showing more than males; neuromedin U-like immunoreactivity was present in some thyrotropes and most corticotropes, in both sexes. Where galanin, neuromedin U and ACTH immunoreactivities were colocalized in corticotropes they were present in the same granules. Estrogen administration caused an increase in number of galanin immunoreactive lactotropes, as previously shown. The proportion of neuromedin U-positive corticotropes was not affected. After adrenalectomy, only females showed a significant increase in the proportion of galanin-positive corticotropes. Neuromedin U immunoreactivity was significantly increased in both sexes, as previously shown. Thus, in rat, as in man, galanin can be present in corticotropes and its expression appears to be sexrelated. This finding, and the demonstration of thyrotrope neuromedin U (only examined in normal females), provide correlation with previous experiments. The influence of endocrine status on the expression of these novel peptides underlines the inherent plasticity of pituitary endocrine cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00323579
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 77
    Electronic Resource
    Electronic Resource
    Endothelial cell connecting filaments anchor endothelial cells to the subjacent elastic lamina in the developing aortic intima of the mouse (1993)
    Springer
    Cell & tissue research 272 (1993), S. 211-219 
    Details
    ISSN: 1432-0878
    Keywords: Aorta ; Endothelium ; Anchoring filaments ; Microfibrils ; Elastin ; Electron microscopy ; Mouse (C57/BL)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The ultrastructural association of endothelial cells with the subjacent elastic lamina was investigated in the developing mouse aorta by electron microscopy. In the 5-day postnatal aorta, extensive filament bundles extend along the subendothelial matrix connecting the endothelial cells to the underlying elastic lamina. The connecting filaments form lateral associations with the abluminal surface of the endothelial cells in regions of membrane occupied by membrane-associated dense plaques. On the intracellular face of each plaque, the termini of stress fibers penetrate and anchor to the cell membrane in alignment with the extracellular connecting filaments. Both the stress fibers and the connecting filaments are oriented parallel to the longitudinal axis of the vessel. High magnification electron micrographs of individual endothelial cell connecting filaments reveal features similar to those of elastin-associated microfibrils. Each connecting filament consists of a 9–10 nm linear core with an electron-lucent center and peripheral spike-like projections. From the filaments, small thread-like extensions span laterally, linking the filaments into a loose bundle and anchoring them to the endothelial cell membrane and the surface of the elastic lamina. The filaments also appear heavily coated with electron-dense material; often with some degree of periodicity along the filament length. During development, the number of endothelial cell connecting filaments decreases as the elastic lamina expands and the subendothelial matrix is reduced. In the aortic intima of mature mice, the elastic lamina is closely apposed to the abluminal surface of the endothelial cell and no connecting filaments are seen. These observations suggest that endothelial cell connecting filaments are developmental features of the aortic intima which, together with the intracellular stress fibers, aid to maintain the structural integrity of the endothelial cell layer during development by providing the cells with protection from intraluminal shear forces.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00302726
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 78
    Electronic Resource
    Electronic Resource
    Structure-activity relationships in corpora allata of the cockroach Diploptera punctata: roles of mating and the ovary (1993)
    Springer
    Cell & tissue research 274 (1993), S. 279-293 
    Details
    ISSN: 1432-0878
    Keywords: Corpora allata ; Electron microscopy ; Morphometry ; Ovariectomy ; Juvenile hormone ; Cockroach, Diploptera punctata (Insecta)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Morphometric studies were made on corpora allata of the cockroach Diploptera punctata from animals in which increasing gland size is not coupled to hormone synthesis (ovariectomized mated females; last-instar larvae) and in which gland size is coupled to hormone synthesis (normal mated and virgin females; penultimate-instar larvae). Cell number, gland volume, and juvenile hormone synthesis were measured. From electron micrographs, nuclear, cytoplasmic, and extracellular volumes; and cell membrane area were calculated; and fine structure described. Low-activity glands of ovariectomized mated females resembled high-activity glands from mated females in high cell number, large overall and cytoplasmic volume, and low nuclear-cytoplasmic ratio; they differed in having organelles typical of low-activity glands, mitochondria with dense matrices and large whorls of smooth endoplasmic reticulum. Inactive lastinstar larval glands resembled mated ovariectomized, female glands in increased cell number and organelles characteristic of inactive glands; however, their nuclearcytoplasmic volume ratio was much higher. Penultimate cytoplasmic volume ratio was much higher. Penultimate larval glands with high activity per cell resembled active glands of normal mated females. Ovariectomy did not change morphometric parameters of virgin female glands; thus mating results in increase in size of adult female glands whereas the growing ovary is needed for changes in mitochondria and endoplasmic reticulum associated with high juvenile hormone synthesis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00318747
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 79
    Electronic Resource
    Electronic Resource
    Scanning and transmission electron-microscopic study of peripolar cells in the newborn lamb kidney (1993)
    Springer
    Cell & tissue research 274 (1993), S. 597-604 
    Details
    ISSN: 1432-0878
    Keywords: Peripolar cells ; Juxtaglomerular apparatus ; Cytoplasmic granules ; Exocytosis ; Electron microscopy ; Sheep, newborn
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Scanning and transmission electron microscopy were used to study the ultrastructural characteristics and positions of granulated peripolar cells in newborn lamb kidney. Following tissue fixation by vascular perfusion in situ, the vascular pole region of the glomerulus was exposed for examination by scanning electron micoscopy following removal of the glomerular tuft. Peripolar cells were recognized by their surface morphology enabling their quantification and an assessment of the relationship of their position in the renal cortex. The prominent expression of peripolar cells in this species was confirmed. Almost every vascular pole examined revealed peripolar cells (405 out of 407; 99.5%) and thus, throughout the cortex, the distribution of peripolar cells was the same as the distribution of renal corpuscles. Larger, more protruding peripolar cells were observed in the outer cortical renal corpuscles. The numbers of peripolar cells encircling each vascular pole ranged from 1 to 10. There was no correlation between number of granulated peripolar cells at the vascular pole and the position of the renal corpuscle within the renal cortex. As viewed by transmission electron microscopy, organelles of protein synthesis were abundant in the cytoplasm of peripolar cells. Exocytosis of cytoplasmic granules was observed by both scanning and transmission electron microscopy implying that a process of regulative secretion occurs from these cells. The use of ultrastrural techniques has provided evidence supporting the concept that peripolar cells are prominent in the cuff region of each renal corpuscle of the newborn lamb and further-more that peripolar cells in this species most likely have a secretory function.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00314558
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 80
    Electronic Resource
    Electronic Resource
    Collagen fibrillogenesis in a three-dimensional fibroblast cell culture system (1993)
    Springer
    Cell & tissue research 273 (1993), S. 571-575 
    Details
    ISSN: 1432-0878
    Keywords: Collagen fibril ; Three dimensional cell culture ; Ascorbate ; Aminopropeptide, type I ; Aminopropeptide, type III ; Electron microscopy ; Immunoelectron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The purpose of this study was to follow collagen fibril formation in a newly developed three dimensional cell culture system. Human neonatal foreskin fibroblasts were grown on a nylon mesh in Dulbecco's Modified Eagles Medium (DMEM) supplemented with 10% fetal calf serum and antibiotics. Fibrillogenesis was initiated by the addition of 50 micrograms/ml ascorbate to confluent cultures. Sample meshes were processed for electron microscopy or immuno-electron microscopy. Fibrils ≈20–30 nm in diameter, with 67 nm periodicity, were first detected five days after the addition of ascorbate. As cultures progressed, cells organized into parallel layers between which collagen fibers continued to form and increase in diameter. By day 50, fiber diameter ranged from 30 to 80 nm and large bundles were seen. No collagen fibril formation occurred in control cultures to which no ascorbate was added. However, large amounts of microfibrils were observed. Antibodies against the aminopropeptide of type I procollagen were found to bind to fibrils with diameters less than 34 nm while antibodies against the aminopropeptide of type III collagen bound primarily to fibers which ranged from 35–54 nm in diameter. We believe that this system, which morphologically resembles a normal dermis, will werve as an excellent model for the study of collagen fibrillogenesis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00333710
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 81
    Electronic Resource
    Electronic Resource
    Some horizontal cells of the bovine retina receive input synapses in the inner plexiform layer (1993)
    Springer
    Cell & tissue research 272 (1993), S. 447-457 
    Details
    ISSN: 1432-0878
    Keywords: Horizontal cells ; Calcium-binding protein ; Synaptie input ; Inner plexiform layer ; Immunoreactivity ; Electron microscopy ; Bovine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Bovine retinae were stained immunocytochemically with antibodies against the calcium-binding protein, calbindin. Horizontal cells in the outer plexiform layer were heavily labelled. The processes of most horizontal cells were confined to the level of the outer plexiform layer, and the tips of their dendrites were positioned as the lateral elements of the cone triads, viz. the usual mammalian arrangement. However, some of the horizontal cells had additional thick processes descending to branch within the inner plexiform layer, where they were postsynaptic at bipolar cell dyads and where they also received input from amacrine cells. No output synapses of horizontal cells were observed in the inner plexiform layer.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00318551
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 82
    Electronic Resource
    Electronic Resource
    Basic fibroblast growth factor-like immunoreactivity in the rat trigeminal sensory system and peri-oral skin with vibrissae (1993)
    Springer
    Cell & tissue research 272 (1993), S. 417-427 
    Details
    ISSN: 1432-0878
    Keywords: Basic fibroblast growth factor ; Trigeminal ganglion ; Immunohistochemistry ; Electron microscopy ; In situ hybridization histochemistry ; Vibrissae ; Hair ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract We have characterized an antiserum against basic fibroblast growth factor (bFGF) by immunoblot, investigated the location of bFGF-like immunoreactivity (bFGF-IR) in the trigeminal sensory system and perioral skin endowed with vibrissae, and demonstrated the site of bFGF mRNA expression in the vibrissae by in situ hybridization histochemistry. Light-microscopic immunohistochemistry has demonstrated that bFGF-IR is present not only in trigeminal ganglion neurons and their central and peripheral processes, but also in cells of the matrix, external root sheath and papillae of vibrissae and the stratum basale of the stratified squamous epithelium of the skin. Electron microscopy has revealed intense bFGF-IR mainly in cytoplasmic regions, other than the lumen of rough endoplasmic reticulum and the Golgi apparatus, in trigeminal ganglion neurons, in fibroblast-like cells in the papillae, and in capsules of vibrissae. In contrast, actively proliferating and/or differentiating cells in the matrix of vibrissae have intensely stained euchromatin and weakly labeled cytoplasm that, unlike that of the aforementioned cells, contain immunoreaction products in discrete spots less than 100 nm in diameter, implying the generation of different molecular forms of bFGF in cells of the matrix and papillae. Moreover, the accumulation of bFGF in the euchromatin appears to take place in cells at non-mitotic stages (possibly interphases), characterized by a conspicuous nucleolus and well-developed nuclear envelope. A digoxigenin-labeled cRNA probe for the demonstration of bFGF mRNA gives conspicuous hybridization signals mainly in the matrix of vibrissae. These findings suggest that bFGF is involved in the growth and differentiation of matrix cells during certain periods of the cell cycle and that it acts as a non-mitogenic mediator in the adult trigeminal sensory system.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00318548
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 83
    Electronic Resource
    Electronic Resource
    Evidence that an extrahypothalamic pituitary corticotropin-releasing hormone (CRH)/adrenocorticotropin (ACTH) system controls adrenal growth and secretion in rats (1993)
    Springer
    Cell & tissue research 272 (1993), S. 439-445 
    Details
    ISSN: 1432-0878
    Keywords: Adrenal growth ; CRH ; ACTH ; Hypophysectomy ; Electron microscopy ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Within two weeks, hypophysectomy induced in rats a striking decrease in the level of circulating ACTH (the concentration of which was at the limit of sensitivity of our assay system), coupled with a net reduction in the plasma corticosterone concentration and an evident adrenal atrophy. Zona fasciculata, the main producer of glucocorticoids, was decreased in volume, due to a lowering in both the number and average volume of its parenchymal cells. Subcutaneous ACTH infusion (0.1 pmol·min-1), administered during the last week following hypophysectomy, restored the normal blood level of ACTH and completely reversed all effects of hypophysectomy on the adrenals. Subcutaneous infusion for one week with α-helical-CRH or corticotropin-inhibiting peptide (1 nmol·min-1), which are competitive inhibitors of CRH and ACTH, evoked a further significant lowering of plasma corticosterone concentration and markedly enhanced adrenal atrophy in hypophysectomized rats. These findings strongly suggest that an extrahypothalamic pituitary CRH/ACTH system may be involved in the maintenance of the growth and steroidogenic secretory activity of the rat adrenal cortex.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00318550
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 84
    Electronic Resource
    Electronic Resource
    Serotoninergic innervation of the alimentary canal of the Colorado potato beetle, Leptinotarsa decemlineata: structural and functional aspects (1993)
    Springer
    Cell & tissue research 273 (1993), S. 475-485 
    Details
    ISSN: 1432-0878
    Keywords: Serotonin ; Alimentary canal, insect ; Stomatogastric neryous system ; Immunohistochemistry ; Bioassay ; Electron microscopy ; Leptinotarsa decemlineata (Insecta)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Immunohistochemical studies showed that the alimentary canal of Leptinotarsa decemlineata receives serotoninergic innervation from different neurons in the central and stomatogastric nervous system. The foregut is innervated by the frontal ganglion. Four of the 6–8 large neurons present in this ganglion have axons which run to the musculature of the oesophagus, crop, sphincter, and frontal area of the midgut. They are accompanied by axons from neurons in the suboesophageal ganglion, and by axons from as yet unidentified non-immunoreactive neurons in thebrain and/or the ventral nerve cord. The posterior part of the midgut is essentially devoid of serotoninergic innervation. The hindgut is innervated by two large neurons in the caudal tip of the last abdominal ganglion. The axons always run to the circular and longitudinal muscles of the crop, the circular muscles of the sphincter, and the longitudinal muscles of the hindgut. Immunohistochemical electron microscopy suggests that exocytosis of the immuno-labelled vesicles may occur at some distance from the muscle fibres, implying a neurohormonal release of this neurochemical. A bioassay used to demonstrate the type of effect of serotonin on isolated hindguts in vitro, indicated a clear inhibitory effect on spontaneous contractions at concentrations of 10-8–10-5 M. This effect was dose-dependent. Axons found in association with the cryptonephridial system on the hindgut might be involved in the control of diuresis although we have not tested this possibility experimentally.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00333702
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 85
    Electronic Resource
    Electronic Resource
    Diffuse serotoninergic neurohemal systems associated with cerebral and suboesophageal nerves in the head of the Colorado potato beetle Leptinotarsa decemlineata (1993)
    Springer
    Cell & tissue research 273 (1993), S. 327-333 
    Details
    ISSN: 1432-0878
    Keywords: Serotonin (5-HT) ; Neurohemal systems ; Immunohistochemistry ; Electron microscopy ; Targeted release ; Leptinotarsa decemlineata (Insecta)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract We analyzed the anatomy of two diffuse neurohemal systems for serotonin in the head of the Colorado potato beetle Leptinotarsa decemlineata by means of immunohistochemistry. One system is formed by axons from two bilateral pairs of neurons in the frontal margin of the suboesophageal ganglion that enter the ipsilateral mandibular nerve, emerge from this nerve at some distance from the suboesophageal ganglion, and cover all branches of the mandibular nerve with a dense plexus of immunoreactive axon swellings. The other system is formed by axons from two large neurons in the frontal ganglion that enter the ipsilateral frontal connectives, emerge from these connectives, and form a network of axon swellings on the labroforntal, pharyngeal, and antennal nerves and on the surface of the frontal ganglion. Immunohistochemical electron microscopy demonstrated that the axon swellings are located outside the neural sheaths of the nerves and hence in close contact with the hemolymph. We therefore suggest that these plexuses represent extensive neurohemal systems for serotonin. Most immunoreactive terminals are in direct contact with the hemolymph, and other terminals are closely associated with the muscles of the mandibles, labrum, and anterior pharynx, as well as with the salivary glands, indicating that these organs are under serotoninergic control.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00312835
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 86
    Electronic Resource
    Electronic Resource
    The metathoracic wing-hinge chordotonal organ of an atympanate moth, Actias luna (Lepidoptera, Saturniidae): a light- and electron-microscopic study (1992)
    Springer
    Cell & tissue research 267 (1992), S. 455-471 
    Details
    ISSN: 1432-0878
    Keywords: Chordotonal organ ; Scolopidium ; Homology ; Electron microscopy ; Sensilla ; Evolution ; Actias luna (Insecta)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The structure of a simple chordotonal organ, the presumed homologue of the noctuoid moth tympanal organ, is described in the atympanate moth, Actias luna. The organ consists of a proximal scolopidial region and a distal strand, which attaches peripherally to the membranous cuticle ventral to the hindwing alula. The strand is composed of elongate, microtubule-rich cells encased in an extracellular connective tissue sheath. The scolopidial region houses three mononematic, monodynal scolopidia, each comprised of a sensory cell, scolopale cell, and attachment cell. The dendritic apex is octagonally shaped in transverse section, its inner membrane lined by a laminated structure reminiscent of the noctuoid tympanal organ ‘collar’. A 9+0-type cilium emerges from the dendritic apex, passes through both the scolopale lumen and cap, and terminates in an extracellular space distal to the latter. Proximal extensions of the attachment cell and distal prolongations of the scolopale cell surrounding the cap are joined by an elaborate desmosome, with which is associated an extensive electron-dense fibrillar plaque. Within the scolopale cell, this plaque constitutes the scolopale ‘rod’ material. The data are discussed in terms of both the organ's potential function, and its significance as the evolutionary proto-type of the noctuoid moth ear.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00319368
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 87
    Electronic Resource
    Electronic Resource
    Synaptic contacts of tyrosine hydroxylase-immunoreactive elements in the inner plexiform layer of the retina of Bufo marinus (1992)
    Springer
    Cell & tissue research 267 (1992), S. 525-534 
    Details
    ISSN: 1432-0878
    Keywords: Retina ; Dopaminergic neurons ; Synapses ; Inner plexiform layer ; Immunocytochemistry ; Electron microscopy ; Bufo marinus (Anura)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Tyrosine hydroxylase (TH) immunocytochemistry was utilized to quantify dopaminergic synapses in the inner plexiform layer of the retina of Bufo marinus. Since dopaminergic cells have bistratified dendritic arborisation in the inner plexiform layer, attention was given to the segregation of synapses between the scleral and the vitreal sublaminae. Light-microscopically, a more elaborate dendritic branching was observed in the scleral than in the vitreal sublamina. In contrast, about 55% of synapses occurred in the vitreal one fifth of the inner plexiform layer, 30% in the scleral fifth, and 15% in the intermediate laminae. Input sources and output targets showed only minor quantitative differences between sublaminae 1 and 5. TH-immunoreactive processes were found in presynaptic (62.8%) and postsynaptic (37.2%) positions. Synapses to the stained dendrites derived from bipolar (40.4%) and amacrine (59.6%) cells, whereas outputs from the TH-positive processes were directed to amacrine cells (56.8%) and to small and medium-sized dendrites (35.4%); at least some of these can be considered as ganglion cell dendrites. TH-positive profiles neither formed synapses with each other nor were presynaptic to bipolar cell terminals. Junctional appositions of the immunoreactive profiles were occasionally seen on non-stained amacrine and ganglion cell dendrites in the scleral sublamina of the inner plexiform layer and on optic axons in the optic fibre layer. Although dopaminergic cells are mainly involved in amacrine-amacrine interactions, inputs from bipolar terminals and outputs to ganglion cell dendrites were also substantial, suggestive of a role also in vertical information processing.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00319375
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 88
    Electronic Resource
    Electronic Resource
    Cellular differences in the regeneration of murine skeletal muscle: a quantitative histological study in SJL/J and BALB/c mice (1992)
    Springer
    Cell & tissue research 269 (1992), S. 159-166 
    Details
    ISSN: 1432-0878
    Keywords: Regeneration ; Skeletal muscle ; Injury ; Autoradiography ; Morphometry ; Electron microscopy ; Mouse (SJL/J BALB/c)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Skeletal muscle regeneration in SJL/J and BALB/c mice subjected to identical crush injuries is markedly different: in SJL/J mice myotubes almost completely replace damaged myofibres, whereas BALB/c mice develop fibrotic scar tissue and few myotubes. To determine the cellular changes which contribute to these differential responses to injury, samples of crushed tibialis anterior muscles taken from SJL/J and BALB/c mice between 1 and 10 days after injury were analysed by light and electron microscopy, and by autoradiography. Longitudinal muscle sections revealed about a 2-fold greater total mononuclear cell density in SJL/J than BALB/c mice at 2 to 3 days after injury. Electron micrographs identified a similar proportion of cell types at 3 days after injury. Autoradiographic studies showed that the proportions of replicating mononuclear cells in both strains were similar: therefore greater absolute numbers of cells (including muscle precursors and macrophages) were proliferating in SJL/J muscle. Removal of necrotic muscle debris in SJL/J mice was rapid and extensive, and by 6 to 8 days multinucleated myotubes occupied a large part of the lesion. By contrast, phagocytosis was less effective in BALB/c mice, myotube formation was minimal, and fibrotic tissue conspicuous. These data indicate that the increased mononuclear cell density, more efficient removal of necrotic muscle, together with a greater capacity for myotube formation in SJL/J mice, contribute to the more successful muscle regeneration seen after injury.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00384736
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 89
    Electronic Resource
    Electronic Resource
    Differential localization of leu-enkephalin and hyperglycemic hormone in axon terminals of the sinus gland of the crabsCarcinus maenas, eriocheir sinensis, andUca pugilator (1992)
    Springer
    Cell & tissue research 270 (1992), S. 521-526 
    Details
    ISSN: 1432-0878
    Keywords: Enkephalins ; Neuropeptides ; Neurohemal organ ; Immunogold ; Electron microscopy ; Carcinus maenas, Uca pugilator, Eriocheir sinensis (Crustacea)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Leu-enkephalin containing secretory granules were demonstrated in axon terminals of immunogoldlabeled electron-microscopic sections of the sinus gland of three brachyuran crustaceans. These granules have a diameter of 120+-15 nm and differ in electron density from those located in adjacent terminals containing hyperglycemic or molt-inhibiting hormone. These neurohormones do not show co-localization with leu-enkephalin. The cross-reactivity of leu-enkephalin antiserum with met-enkephalin is less than 1%. The sinus glands of the three species examined show no immunoreactivity for FMRF-amide. A modulatory activity of endogenous enkephalin by paracrine mechanisms is suggested.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00645054
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 90
    Electronic Resource
    Electronic Resource
    Immuno-electron-microscopic localization of basic fibroblast growth factor in the dystrophic mdx mouse masseter muscle (1992)
    Springer
    Cell & tissue research 270 (1992), S. 569-576 
    Details
    ISSN: 1432-0878
    Keywords: Basic fibroblast growth factor ; Regeneration ; Degeneration ; Immunohistochemistry ; Electron microscopy ; Masseter muscle ; Myoneural junction ; Mouse (dystrophic mdx)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The localization of basic fibroblast growth factor (bFGF)-like immunoreactivity in the masseter muscle of dystrophic mdx mice on postnatal day 28 was investigated by immunoblot analysis and electron microscopy. Crude homogenate of the masseter muscle, when subjected to immunoblotting with a bFGF antiserum, exhibited a main band with the same molecular weight (18 kDa) as bovine bFGF. By electron microscopy, bFGF immunoreactivity was detected in small regenerating myocytes; the smaller cells were the premature myocytes, the most intense staining was the immunoreactivity within the cytoplasm. Putative precursors of the muscle cells with a few myofilaments, which were most intensely labeled with anti-bFGF, contacted each other and possibly developed into multinucleated myocytes through cell fusion. Mature myocytes with densely packed myofilaments and peripherally located nuclei did not exhibit bFGF immunoreactivity; they formed myoneural junctions with motor nerve endings immunoreactive for bFGF. Early differentiating myocytes with intense bFGF-like immunoreactivity did not make contact with immunoreactive nerve terminals. Degenerating large myocytes with a limited number of distorted and/or disrupted myofilaments exhibited electron-dense deposits in the cristae of mitochondria; these deposits were not abolished by immunoadsorption control experiments. Thus, the cell-size-dependent decrease in bFGF immunoreactivity in regenerating but not in degenerating myocytes provides a morphological basis for an autoregulatory role of bFGF in muscle regeneration. This study suggests that neuronal bFGF is not involved in initial muscle regeneration in the dystrophic mdx mouse.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00645060
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 91
    Electronic Resource
    Electronic Resource
    Ovarian innervation develops before initiation of folliculogenesis in the rat (1992)
    Springer
    Cell & tissue research 270 (1992), S. 87-93 
    Details
    ISSN: 1432-0878
    Keywords: Ovarian nerves ; Development ; Folliculogenesis ; Tyrosine hydroxylase ; Immunohistochemistry ; Electron microscopy ; Rat (Sprague Dawley)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Sympathetic neurotransmitters have been shown to be present in the ovary of the rat during early postnatal development and to affect steroidogenesis before the ovary becomes responsive to gonadotropins, and before the first primordial follicles are formed. This study was undertaken to determine if development of the ovarian innervation is an event that antedates the initiation of folliculogenesis in the rat, Rattus norvegicus. Serial sections of postnatal ovaries revealed a negligible frequency of follicles 24 h after birth (about 1 primordial follicle per ovary). Twelve hours later there were about 500 follicles per ovary, a number that more than doubled to about 1300 during the subsequent 12 h, indicating that an explosive period of follicular differentiation occurs between the end of postnatal days 1 and 2. Electron microscopy demonstrated that before birth the ovaries are already innervated by fibers containing clear and dense-core vesicles. Immunohistochemistry performed on either fetal (day 19) or newborn (less than 15h after birth) ovaries showed the presence of catecholaminergic nerves, identified by their content of immunoreactive tyrosine hydroxylase (TH), the rate-limiting enzyme in catecholamine biosynthesis. While some of these fibers innervate blood vessels, others are associated with primordial ovarian cells, thereby suggesting their participation in non-vascular functions. Since prefollicular ovaries are insensitive to gonadotropins, the results suggest that the developing ovary becomes subjected to direct neurogenic influences before it acquires responsiveness to gonadotropins.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00381883
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 92
    Electronic Resource
    Electronic Resource
    The effects of ageing on the morphology and function of the zonae fasciculata and reticularis of the rat adrenal cortex (1992)
    Springer
    Cell & tissue research 270 (1992), S. 265-272 
    Details
    ISSN: 1432-0878
    Keywords: Adrenal cortex ; Ageing ; Steroidogenesis ; Electron microscopy ; Morphometry ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The morphological counterpart of the well-known age-dependent marked impairment of glucocorticoid secretion of rat adrenals was investigated by use of morphometric techniques. For this purpose 4-, 8-, 16- and 24-month-old rats were studied. Despite the notable lowering of both basal and ACTH-stimulated production of corticosterone by collagenase-dispersed inner adrenocortical cells, ACTH and corticosterone plasma concentrations displayed significant increases with ageing. Zona fasciculata (ZF) and zona reticularis (ZR) showed a notable hypertrophy in aged rats, which was due to rises in both the average volume and number of their parenchymal cells. The hypertrophy of ZF and ZR cells was in turn associated with increase in the volume of the mitochondrial compartment and proliferation of smooth endoplasmic reticulum, i.e., the two organelles involved in steroid-hormone synthesis. All these morphologic changes, conceivably due to the chronic exposure to high levels of circulating ACTH, are interpreted as a response enabling ZF and ZR to compensate for their age-dependent lowering in glucocorticoid secretion. Stereology also demonstrated that ZF and ZR cells underwent a striking age-related lipid-droplet repletion. Lipid droplets are the intracellular stores of cholesterol esters, the obligate precursors of steroid hormones in rats. This finding is in keeping with the contention that the mechanism underlying the age-dependent decline in rat-adrenal glucocorticoid secretion mainly involves impairments of the utilization of intracellular cholesterol previous to its intramitochondrial transformation to pregnenolone.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00328012
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 93
    Electronic Resource
    Electronic Resource
    Characterization of macrophage-like cells in the external layers of human small and large intestine (1992)
    Springer
    Cell & tissue research 270 (1992), S. 273-279 
    Details
    ISSN: 1432-0878
    Keywords: Macrophages ; Small intestine ; Large intestine ; External muscle layer ; Immunohistochemistry ; Histochemistry ; Electron microscopy ; Man
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In the external layers of human small and large intestine macrophage-like cells were characterized by immunohistochemical, histochemical and electronmicroscopical methods. Using immunohistochemistry and a number of monoclonal antibodies, the presence and distribution of phenotypic subpopulations of macrophages were evaluated. In all locations macrophage-like cells were identified with antibody EBM11, which recognizes CD68 antigen, C3bi which recognizes CD11b, and partly with an antibody which recognizes protein 150,95 (CD11c). Macrophage-like cells in the external muscle layer were HLA-DR-positive (expressing the MHC class-II antigen), in contrast to macrophage-like cells in the subserosa and submucosa. Macrophage-like cells in the external muscle layer were mostly acid phosphatase-negative, and at the electron-microscopic level they were found to have features of macrophages: primary lysosomes, coated vesicles and pits. However, very few secondary lysosomes were present. Birbeck granules were not observed. It is concluded that in the external muscle layer of human small and large intestine numerous macrophages of a special type are present. It is discussed whether this cell type plays a role in gastrointestinal motility and/or has an immunological function.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00328013
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 94
    Electronic Resource
    Electronic Resource
    Initial formation of cellular intrinsic fiber cementum in developing human teeth (1992)
    Springer
    Cell & tissue research 267 (1992), S. 321-335 
    Details
    ISSN: 1432-0878
    Keywords: Teeth ; Cementum ; Cementoblasts ; Matrix production ; Electron microscopy ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The present study describes the formative process of the initiation of cellular intrinsic fiber cementum (CIFC) in still growing human teeth. From 29 premolars and molars with incomplete roots developed to 60–90% of their final length, 8 premolars (with roots formed to three quarters of their final length) were selected for electron-microscopic investigation. All teeth were clinically intact and prefixed in Karnovsky's fixative immediately after extraction. Most of them were decalcified in ethylene diaminetetraacetic acid (EDTA), and the apical part of the roots was divided axially into mesial and distal portions that were subdivided in about 5 slices each. Following osmication and embedding in Epon, these blocks were cut for light- and electron-microscopic examination. In addition, 5 teeth with incomplete roots were freed from organic material and processed for scanning electron microscopy. It was found that CIFC-initiation commenced very close to the advancing root edge and resulted in a rapid cementum thickening. Thereafter, appositional growth continued on the already established cementum surface. Large, basophilic and rough endoplasmic reticulum-rich cementoblasts, some of which became cementocytes, were responsible for both fast and slow CIFC-formation. The CIFC-matrix was free of Sharpey's fibers and composed of more or less organized intrinsic collagen fibrils, in part fibril bundles, that ran roughly parallel to the root surface. Initially, the cementum fibrils intermingled with those of the dentinal collagen fibrils, which were not yet mineralized. This boundary subsequently underwent calcification. The development of collagen fibril bundles and their extracellular arrangement were associated with cytoplasmic processes probably involved in fibril formation and fibril assembly. Many cementoblasts contained intracytoplasmic, membrane-bounded collagen fibrils, which probably were related to fibril formation rather than degradation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00302971
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 95
    Electronic Resource
    Electronic Resource
    Development of cytoplasmic digitations between Leydig cells and testicular macrophages of the rat (1992)
    Springer
    Cell & tissue research 267 (1992), S. 385-389 
    Details
    ISSN: 1432-0878
    Keywords: Leydig cells ; Macrophages ; Development, ontogenic ; Electron microscopy ; Testis ; (Rat Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Testicular macrophages and Leydig cells from adult animals are known to be functionally coupled. For example, secreted products from macrophages stimulate testosterone secretion by Leydig cells. In adult rat testes, structural coupling also exists between these cells. This coupling consists of cytoplasmic projections from Leydig cells located within cytoplasmic invaginations of macrophages. Although macrophages are known to exist in the testis in immature animals, it is not known when these digitations develop. The purpose of the present study was to determine whether the time of their development coincides with known maturational events that occur in Leydig cells, particularly during the peripubertal period. Testes from rats at 20, 30 and 40-days-of-age as well as testes from mature rats weighing more than 500 gm were prepared for ultrastructural analysis. It was found that digitations form between 20 and 30-days-of-age. These structures varied from simple tubular projections to complicated branched structures, suggesting that digitations are more than simple invaginations of microvilli into coated vesicles as previously described. Subplasmalemmal linear densities were also observed within macrophages juxtaposed to Leydig cells. Collagen was commonly observed between macrophages and Leydig cells in animals 20 days old. These studies demonstrate that although macrophages are present in the testis in maximal numbers at 20 days-of-age, they do not form junctions with Leydig cells until day 30. This is just prior to the major increase in secretory activity of rat Leydig cells that occurs during puberty.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00302977
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 96
    Electronic Resource
    Electronic Resource
    Interstitial cells associated with the deep muscular plexus of the guinea-pig small intestine, with special reference to the interstitial cells of Cajal (1992)
    Springer
    Cell & tissue research 268 (1992), S. 205-216 
    Details
    ISSN: 1432-0878
    Keywords: Intestine ; Interstitial cells ; Pacemaker ; Electron microscopy ; Guinea-pig
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Interstitial cells associated with the deep muscular plexus of the guinea-pig small intestine were studied by electron microscopy, and three-dimensional cell models were reconstructed from serial ultrathin sections with a computer graphic system. Three types of cells were recognized. The first type was similar in shape to smooth muscle cells, but did not contain an organized contractile apparatus. Many large gap junctions comprising about 4% of the cell surface were present; they connected cells of the first type to each other, to the second type of cell and to smooth muscle cells of the outer circular layer. The second type of cell had a welldemarcated cell body with long slender processes and was characterized by a large amount of glycogen comprising about 9% of the cell volume. The third type of cell was similar to fibroblasts, and contained well-developed Golgi apparatus and rough endoplasmic retiulum. Some of these fibroblast-like cells (a possible subtype) formed small gap junctions. All three types of cells showed close relationships with nerve varicosities. This cellular network consisting of gap-junction-rich cells, glycogen-rich cells and smooth muscle cells may be involved in the pacemaking activity of intestinal movement.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00318788
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 97
    Electronic Resource
    Electronic Resource
    12-O-tetradecanoylphorbol-13-acetate induces selective desquamation of superficial cells in rat urinary bladder epithelium (1992)
    Springer
    Cell & tissue research 268 (1992), S. 239-245 
    Details
    ISSN: 1432-0878
    Keywords: Urinary bladder ; Epithelial desquamation ; TPA ; Electron microscopy ; Rat (Donryu)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary 12-O-tetradecanoylphorbol-13-acetate (TPA) is known to affect the proliferation and/or differentiation of several types of cells. We injected TPA directly into the lumen of rat bladder to determine, using scanning and transmission electron microscopy, its effects on the bladder epithelium in vivo. At 1 h after TPA injection (1μg/ml), the superficial cells of the epithelium had changed their morphology, and large spherical vacuoles occupied their cytoplasm. In some areas, the underlying intermediate cells were exposed by the desquamation of the superficial cells. During the next few hours, TPA was excreted from the bladder lumen by voluntary micturition, but the desquamation of the superficial cells proceeded further. All the superficial cells were lost from the luminal surface by 24 h after TPA injection. The changes noted were specific for the superficial cells and were not observed in the intermediate or basal cells. After 24h, part of the epithelium had a three-layer structure, indicating that regeneration was taking place. These results demonstrate that TPA selectively affects and desquamates superficial cells in a short period of time. This experimental system may be useful for studying in vivo cell proliferation and/or differentiation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00318792
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 98
    Electronic Resource
    Electronic Resource
    Histomorphological aspects of vascular anastomosis established by laser (1991)
    Springer
    Lasers in medical science 6 (1991), S. 363-366 
    Details
    ISSN: 1435-604X
    Keywords: Laser vascular welding ; Tissue fusion ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Physics , Technology
    Notes: Abstract The central problem in microsurgery is the reconstruction of small vessels. The long operating time, foreign body granuloma formation around the suture material as well as aneurysmal alterations of the vessel wall after conventional suture technique make the search for alternatives indispensable. Some of these disadvantages can be avoided as demonstrated by our animal experiments and histological examinations in laser-assisted anastomosing. The aim of this study is to show these aspects in connection with laser application and compare them with conventional suture techniques.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02030894
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 99
    Electronic Resource
    Electronic Resource
    A cytochemical and immunocytochemical study of DNA distribution in spermatid nuclei of mouse, rabbit, and bull (1991)
    Springer
    Cell & tissue research 265 (1991), S. 517-525 
    Details
    ISSN: 1432-0878
    Keywords: Spermiogenesis ; Spermatids ; DNA ; Immunocytochemistry ; Electron microscopy ; Bovine ; Mouse ; Rabbit
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary DNA distribution in mouse, rabbit and bull spermatids was analyzed by electron microscopy, after using a Feulgen-like HCl-osmium ammine procedure, and after immunocytochemistry with anti-DNA antibodies. In addition, nucleic acids were visualized with the intercalating dye ethidium bromide and phosphotungstic acid. The parts of DNA displaying a beta helix configuration (possibly A-T rich parts) were identified by epifluorescence microscopy after staining with Hoechst 33258. In all 3 species, young spermatid nuclei were seen to have large areas poor in DNA, as well as DNA-rich areas, which were mostly concentrated into a peripheral layer close to the acrosome and into one or several masses, displaying species-specific locations. These DNA-rich areas were stained with Hoechst 33258. Elongating spermatid nuclei contained homogeneously distributed DNA, and this was evident following both immunocytochemistry and nucleic acid histochemistry in all 3 species. However, the distribution appeared more heterogeneous after the Feulgen-like procedure, and was accompanied by a disappearance of Hoechst-fluorescence. In fully elongated spermatids, all nuclear areas stained with Hoechst 33258, while the 3 other techniques labeled either all or species-specific parts of the condensed chromatin. The reasons for these variable reactions are discussed in terms of technique specificities, DNA configuration and nucleoprotein moiety replacements.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00340875
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 100
    Electronic Resource
    Electronic Resource
    Transient expression of a calcium-binding protein (spot 35-calbindin) and its mRNA in the immature pituicytes of embryonic rats (1991)
    Springer
    Cell & tissue research 266 (1991), S. 325-330 
    Details
    ISSN: 1432-0878
    Keywords: Calbindin ; Neurohypophysis ; Development, ontogenetic ; Immunohistochemistry ; In-situ hybridization ; Electron microscopy ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Spot 35 protein is a Ca-binding protein originating from the rat cerebellum; it is now referred to spot 35-calbindin. This protein is expressed in immature pituicytes of the neurohypophyseal anlage in the E11–E18 rat embryo. The gene expression of spot 35-calbindin was detected by in-situ hybridization analysis only at stage E11–E12. Profiles of spot 35-positive nerve fibers of a neurosecretory nature were found in anlage at stage E16. At this stage, some immature pituicytes are partially immunopositive for spot 35-calbindin only in their peripheral cytoplasm; others are immunonegative. At birth and thereafter through adulthood, abundant nerve fibers are the sole structures immunoreactive for spot 35-calbindin; all the pituicytes are immunonegative, resulting in a light-microscopic appearance of numerous immunonegative round profiles, corresponding to pituicytes, and capillaries embedded in the granularly immunostained neurohypophysis. The present findings suggest that, during specific embryonic stages, immature pituicytes exert some as yet unidentified roles related to Ca-mediated functions involving the expression of spot 35-calbindin.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00318188
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...