ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
Filter
  • Immunocytochemistry  (856)
  • Springer  (856)
  • Blackwell Publishing Ltd
  • American Institute of Physics (AIP)
Collection
Keywords
Publisher
  • 1
    ISSN: 0219-1032
    Keywords: Calcium-binding Protein ; Immunocytochemistry ; Localization ; Visual Cortex
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The distribution and morphology of neurons containing three calcium-binding proteins, calbindin D28K, calretinin, and parvalbumin in the adult rabbit visual cortex were studied. The calcium-binding proteins were identified using antibody immunocytochemistry. Calbindin D28K-immunoreactive (IR) neurons were located throughout the cortical layers with the highest density in layer V. However, calbindin D28K-IR neurons were rarely encountered in layer I. Calretinin-IR neurons were mainly located in layers II and III. Considerably lower densities of calretinin-IR neurons were observed in the other layers. Parvalbumin-IR neurons were predominantly located in layers III, IV, V, and VI. In layers I and II, parvalbumin-IR neurons were only rarely seen. The majority of the calbindin D28K-IR neurons were stellate, round or oval cells with multipolar dendrites. The majority of calretinin-IR neurons were vertical fusiform cells with long processes traveling perpendicularly to the pial surface. The morphology of the majority of parvalbumin-IR neurons was similar to that of calbindin D28K: stellate, round or oval with multipolar dendrites. These results indicate that these three different calcium-binding proteins are contained in specific layers and cells in the rabbit visual cortex.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1615-6102
    Keywords: Arabinogalactan proteins ; Fiber ; Linum usitatissimum ; Immunocytochemistry ; Polysaccharide ; Secondary wall
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The deposition and formation of a thick secondary wall is a major event in the differentiation of flax (Linum usitatissimum) fibers. This wall is cellulose-rich; but it also contains significant amounts of other matrix polymers which are noncellulosic such as pectins. We have used immunocytochemical techniques with antibodies specific for various epitopes associated with either pectins or arabinogalactan proteins (AGPs) to investigate the distribution of these polymers within the walls of differentiating young fibers of 1- and 2-week-old plants. Our results show that different epitopes exhibit distinct distribution patterns within fiber walls. Unesterified pectins recognized by polygalacturonic acid-rhamnogalacturonan I (PGA/RG-I) antibodies and rhamnogalacturonan II recognized by anti-RG-II-borate complex antibodies are localized all over the secondary wall of fibers. PGA/RG-I epitopes, but not RG-II epitopes, are also present in the middle lamellae and cell junctions. In marked contrast, β-(1→4) galactans recognized by the LM5 monoclonal antibody and AGP epitopes recognized by anti-β-(1→6) galactan and LM2 antibodies are primarily located in the half of the secondary wall nearest the plasma membrane. LM2 epitopes, present in 1-week-old fibers, are undetectable later in development, suggesting a regulation of the expression of certain AGP epitopes. In addition, localization of cellulose with the cellobiohydrolase I-gold probe reveals distinct subdomains within the secondary walls of young fibers. These findings indicate that, in addition to cellulose, early-developing flax fibers synthesize and secrete different pectin and AGP molecules.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Trees 13 (1999), S. 138-151 
    ISSN: 0931-1890
    Keywords: Key words Cytoskeleton ; Immunocytochemistry ; Model systems ; Populus ; Secondary vascular system
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract  Trees represent a, probably the, major component of the biosphere and have a unique place in the history of Mankind. One of their most fascinating features is the process of secondary growth which is effected principally by the secondary vascular system, the developmental continuum of secondary phloem, vascular cambium, and secondary xylem. However, for too long assumptions about the developmental biology of trees have had to be based upon studies of primary growth systems within annual, herbaceous species because study of the secondary vascular system had been largely ignored. Even when attempts are made to understand some of the most fundamental features of the secondary vascular system, such as xylogenesis, the current model system, isolated Zinnia mesophyll cells, is not entirely appropriate to the situation in the intact tree. Some deficiencies of the Zinnia system are discussed, and the advantages of the genus Populus as a model for study of the hardwood secondary vascular system are considered. Some of the new approaches which are poised to lead to significant advances in our knowledge of the cell bio-logy of the secondary vascular system of trees – spe-cifically of the cell wall, the plasmalemma, and the cytoskeleton – are discussed. The value of one of these new techniques – immunocytochemistry – is demonstrated by a consideration of recent work on the role of the cytoskeleton in the hardwood secondary vascular system.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    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
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 295 (1999), S. 159-170 
    ISSN: 1432-0878
    Keywords: Key words Neuropeptides ; Perisympathetic organ ; Myotropin ; Visceral muscles ; Immunocytochemistry ; Insect nervous system ; Periplaneta americana (Insecta)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract A highly specific polyclonal antiserum has been raised against periviscerokinin, the first neuropeptide isolated from the perisympathetic organs of insects (Predel et al. 1995). In this study, two different neuronal systems with periviscerokinin-like immunoreactivity were distinguished in the central nervous system of the American cockroach: (1) An intrinsic neuronal network, restricted to the head-thoracic region, was formed by intersegmental projecting neurons of the brain, suboesophageal ganglion and metathoracic ganglion. In addition, groups of local interneurons occurred in the proto- and tritocerebrum. (2) A typical neurohormonal system was stained exclusively in the abdomen; it was represented by abdominal perisympathetic organs which were supplied by three cell clusters located in each unfused abdominal ganglion. As revealed by nickel backfills, most neurons with axons entering the perisympathetic organs contained a periviscerokinin-like peptide. Immunoreactive fibres left the perisympathetic organs peripherally, innervated the hyperneural muscle and ran via the link nerves/segmental nerves to the heart and segmental vessels. All visceral muscles innervated by periviscerokinin-immunoreactive fibres were shown to be sensitive to periviscerokinin, whereas the hindgut gave no specific response to this peptide.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1432-0878
    Keywords: Key words Retina ; NOS ; Immunocytochemistry ; Synaptic connectivity ; Guinea pig
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  Immunocytochemical methods with an antiserum against neuronal nitric oxide synthase (NOS) were applied to identify the morphology and synaptic connectivity of NOS-like immunoreactive neurons in the guinea pig retina. In the present study, two types of amacrine cells were labeled with anti-NOS antisera. Type 1 cells had large somata located in the inner nuclear layer (INL) with long, sparsely branched processes ramifying mainly in stratum 3 of the inner plexiform layer (IPL). The somata of type 2 cells (smaller diameters) were located in the INL. Some displaced amacrine cells in the ganglion cell layer were labeled. The soma size of the displaced amacrine cells was similar to that of the type 2 amacrine cells. However, processes originating from type 2 amacrine cells and displaced amacrine cells stratified mainly in strata 1 and 5, respectively. Some cone bipolar cells were weakly NOS-immunoreactive. The synaptic connectivity of NOS-like immunoreactive amacrine cells was identified in the IPL by electron microscopy. NOS-labeled amacrine cell processes received synaptic input from other amacrine cell processes and bipolar cell axon terminals in all strata of the IPL. The most frequent postsynaptic targets of NOS-immunoreactive amacrine cells were other amacrine cell processes. Cone bipolar cells were postsynaptic to NOS-labeled amacrine cells in all strata of the IPL. Labeled amacrine cells synapsing onto ganglion cells were found only in sublamina b. A few synaptic contacts were observed between labeled cell processes. In the outer plexiform layer, dendrites of labeled bipolar cells made basal contact with cone pedicles or formed a synaptic triad opposed to a synaptic ribbon of cone pedicles.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    ISSN: 1432-0878
    Keywords: Key words Pigment-dispersing hormone ; Immunocytochemistry ; Central nervous system ; Gastropoda ; Helix pomatia ; Lymnaea stagnalis (Mollusca)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract By using an antiserum raised against a crustacean β-pigment-dispersing hormone (PDH), the distribution and chemical neuroanatomy of PDH-like immunoreactive neurons was investigated in the central nervous system of the gastropod snails, Helix pomatia and Lymnaea stagnalis. The number of immunoreactive cells in the Helix central nervous system was found to be large (700–900), whereas in Lymnaea, only a limited number (50–60) of neurons showed immunoreactivity. The immunostained neurons in Helix were characterized by rich arborizations in all central ganglia and revealed massive innervation of all peripheral nerves and the neural (connective tissue) sheath around the ganglia and peripheral nerve trunks. A small number of Helix nerve cell bodies in the viscero-parietal ganglion complex were also found to be innervated by PDH-like immunoreactive processes. Hence, a complex central and peripheral regulatory role, including neurohormonal actions, is suggested for a PDH-like substance in Helix, whereas the sites of action may be more limited in Lymnaea.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 1432-0878
    Keywords: Key words Coagulating gland ; Apocrine secretion ; Merocrine secretion ; Immunocytochemistry ; Immunoelectron microscopy ; Scanning electron microscopy ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The coagulating gland of the rat synthesizes two prevalent secretory proteins (transglutaminase and 115 K) that are discharched in a different manner, one being secreted in an apocrine fashion (transglutaminase) and the other one in a merocrine way (115 K). Differences in the intra- cellular pathway and the release of either protein were studied using immunofluorescence on semithin sections, immunoelectron microscopy of preembedding-processed chopper sections and postembedding-processed ultrathin sections of rat coagulating gland. Immunohistochemical staining using an anti-transglutaminase antibody resulted in dense labeling of the cytoplasm of secretory cells and their apical blebs, whereas the cisternae of the rough endoplasmic reticulum and the Golgi apparatus were completely unlabeled. When, on the contrary, the anti-115 K antiserum was used, dense labeling of the cisternae of the rough endoplasmic reticulum, the Golgi apparatus, and the secretory granules was seen. Intraluminal secretion was also labeled, but the secretory blebs remained unlabeled. Our findings show that, in the coagulating gland of the male rat, the two secretory proteins studied are processed in parallel, but at completely different intracellular pathways. They are released via different extrusion mechanisms. Transglutaminase is synthesized outside the endoplasmic reticulum, reaches the apical cell pole by free flow in the cytoplasm, and is released via apocrine blebs, the membranes of which appear to be derived from the apical plasma membrane. The protein 115 K, on the other hand, follows the classic route, being synthesized within the cisternae of rough endoplasmic reticulum, subsequently glycosylated in the Golgi apparatus, and released in a merocrine fashion. The mutual exclusion of the two secretory pathways and the regulation of the alternative release mechanism are still unresolved issues.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 1432-0878
    Keywords: Key words Cerebrovascular development and injury ; Hemangioma ; Angiogenesis ; Immunocytochemistry ; Adhesion molecules ; Conventional transmission and high-voltage electron microscopy ; Mouse (C57BL ; SJL/J) ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Blood vessels from the vasculature of mouse brains during postnatal development and from human brain tumors (hemangiomas) removed at biopsy were examined immunocytochemically by transmission electron microscopy (TEM) or high-voltage transmission electron microscopy (HVEM) to determine the expression of intercellular adhesion molecule-1 (ICAM-1). In the mouse brains, ICAM-1 was shown to be initially expressed on the luminal and abluminal endothelial cell (EC) surfaces on day 3 after birth. ICAM-1 intensity increased on the luminal EC surfaces and labeled vesiculotubular profiles (VTS, defined in the present report) between days 5 and 7. After 2 weeks and at 6 months after birth, ICAM-1 labeling was weak or absent on the luminal EC surfaces. The hemangiomas presented a strong ICAM-1 reaction product on the luminal EC surfaces of small and large blood vessels associated with the VTS, with a weaker labeling of the abluminal or adventitial aspects of larger blood vessels. TEM of vesiculovacuolar structures (VVOs) within ECs from arteries and veins also demonstrated reaction product for ICAM-1 labeling. Three-dimensional stereo-pair images in the HVEM enhanced the visualization of gold particles that were attached to the inner-delimiting membrane surfaces of EC VTS, and VVOs, respectively. These observations raise the possibility that the neonatal leukocytes and tumor cells may utilize these endothelial structures as a route across the developing and injured blood-brain barrier (BBB).
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 1432-0878
    Keywords: Key words Melanin-concentrating hormone neurons ; Lateral hypothalamic slice culture ; Immunocytochemistry ; Ultrastructure ; In situ hybridization ; Competitive RT-PCR ; Leptin assay ; Rat (Sprague Dawley)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  Hypothalamic slices containing the lateral hypothalamic area (LHA) were prepared from 6- to 8-day-old rats and maintained in stationary culture for up to 35 days in order to analyse how well the melanin-concentrating hormone (MCH) neurons survived. As previously reported for other brain areas, this method yielded a long-term well-preserved organotypic organization. Light- and electron-microscopic investigations showed that differentiation continued and that synaptic contacts developed in vitro. After a period of elimination of damaged cells and fibres, most of the remaining neurons and glial cells retained a normal morphology throughout the culture period. MCH neurons, in particular, survived well as attested by the strong immunocytochemical and in situ hybridization signals still observed after several weeks. In a comparison with the day of explantation, competitive reverse transcription/polymerase chain reaction demonstrated the remarkable stability of the level of MCH mRNA at least until the 20th day in culture; after 30 days, the clear decrease in this level seemed to be correlated with a loss of MCH neurons, rather than with a decrease in MCH expression. After 10 days of culture, the incubation of slices in the presence of the hormone leptin (50 ng/ml) resulted in a strong decrease of MCH gene expression, suggesting that MCH neurons retained their physiological properties. Thus, the LHA slice stationary culture, especially between one and three weeks (i.e. after tissue stabilization and before extensive cell loss), appears to be a suitable method for physiological and pharmacological studies of these neurons.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 11
    ISSN: 1615-6102
    Keywords: Cumulus oophorus ; Ovarian follicle ; Fertilization ; Ultrastructure ; Immunocytochemistry ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The fine structure of the human cumulus oophorus has been reviewed on the basis of scanning and transmission electron microscopic observations as well as of immunofluorescence data. Tissues sampled from preovulatory ovarian follicles and cumulus-enclosed oocytes and fertilized eggs (collected from the oviduct or obtained during in vitro fertilization procedures) have been evaluated from a microtopographic and morphodynamic point of view in order to better clarify the possible role of this population of cells. In particular, the following aspects have been studied and discussed: the presence of multiple close contacts (modulated by the interposition of the zona pellucida) between the oocyte surface and the long microvillous evaginations projecting from the inner aspect of corona cells surface (through these structures the intraovarian cumulus oophorus may control oocyte growth and metabolism up until the time of ovulation); the occurrence of different subpopulations of cells (steroid-synthetic cells, cells producing adhesive proteins, leukocytes, macrophages) in the postovulatory, extraovarian cumulus oophorus surrounding oocytes, zygotes and early developing embryos. All these elements found in the cumulus mass may positively act, through their paracrine activities, on the chemical composition of the microenvironment in which fertilization occurs.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 12
    ISSN: 1615-6102
    Keywords: Floral binding protein ; Flower development ; Immunocytochemistry ; MADS-box genes ; Ovule ; Transcription factors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary DuringPetunia hybrida seed development, the MADS-box genes encoding the floral binding proteins (FBP) 7 and 11 are expressed in the seed coat and not in the endosperm or embryo. These proteins are thought to function as transcription factors and are essential for ovule formation inPetunia spp. Immunocytochemical methods were used to analyze the distribution of FBP7 and FBP11 after fertilization in wild type and ectopic and cosuppression mutants. During the first nine days of seed development the protein was found in the nuclei of seed coat cells, of both wild-type plants and plants which ectopically expressedFBP11. The signal for FBP7 and -11 proteins diminished during seed development, was first lost in the outer epidermis of the seed coat, then in the endothelium, and finally, at 9 days after pollination (DAP), the protein could not be detected anymore in the parenchyma cells of the seed coat. Although the distribution patterns in wild-type andFBP11 ectopically expressing plants are similar, the latter exhibited higher protein levels. A mild-cosuppression mutant ofFBP7 andFBP11, having only a total of 5%FBP7 and -11 mRNA, showed hardly any FBP7 and -11 proteins. The lack of FBP7 and -11 caused endosperm degeneration in the mutant at a moment when the protein had already decreased to an undetectable level in the wild type and ectopic expression mutant (i.e., at 13 DAP). It is suggested that till about 9 DAP a minimal amount of FBP7 and -11 is needed for the normal functioning of the seed coat during later stages, i.e., for transfer of nutrients to endosperm and embryo. Besides the immunocytochemical data on theFBP7 andFBP11 MADS-box gene products, the morphological analysis of wild type and mutants contributes details on early seed development inPetunia hybrida.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 13
    ISSN: 1615-6102
    Keywords: Haustorium ; Immunocytochemistry ; Interface ; Parasitism ; Defense mechanisms ; Scrophulariaceae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The haustorial structure of three African parasitic members of the family Scrophulariaceae (Buchnera hispida, Rhamphicarpa fistulosa, andStriga hermonthica) has been studied with regard to the interface between haustoria and the invaded host roots. Immunocytochemical observations at the light and electron microscopical level were carried out with monoclonal antibodies against pectin. JIM5, JIM7, and hydroxyproline-rich glycoprotein (HRGP), LM1. Lignins have been visualized by phloroglucinolhydrochloric acid staining. At the margin of the lateral interface (contact area of host root cortex and parasite cells), JIM5- and JIM7-labelled substances accumulate between parasite papillae and the host root surface indicating that pectins are implicated in sealing the parasite to the attacked host organ. The lateral interface is characterized by the presence of compressed, necrotic host cells, whereas the central interface (contact area between host stele and parasite cells) is generally devoid of host cell remnants. Phenolic substances and/or lignins can be found at the site of penetration of the haustorium into the host root. These observations and the fact that HRGPs accumulate at the host side of the interface support the view of, at least, a partial defense reaction in the invaded host root tissues. Within haustoria, HRGPs were restricted to differentiating xylem elements, implying a spatio-temporal regulation of HRGPs in developmental processes.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 14
    Electronic Resource
    Electronic Resource
    Springer
    Protoplasma 206 (1999), S. 1-10 
    ISSN: 1615-6102
    Keywords: Arabinogalactan protein ; Cell wall component ; Immunocytochemistry ; Pectin ; Pinus densiflora ; Pollen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary In order to compare cell wall formation in gymnosperm pollen with that in angiosperm pollen, the distribution of cell wall constituents in the pollen grain and pollen tube ofPinus densiflora was studied immunocytochemically with monoclonal antibodies JIM 5 (against non- or poorly esterified pectin), JIM 7 (against highly esterified pectin), JIM 13 (against arabinogalactan proteins, AGPs), and LM 2 (against AGPs containing glucuronic acid). In the pollen grain wall, only the outer layer of the intine was labeled with JIM 5 and weakly with JIM 7. The tube wall was scarcely labeled with JIM 5 and very weakly labeled with JIM 7. In contrast, the whole of both the intine and the tube wall was strongly labeled with JIM 13 and LM 2, and the generative-cell wall was also labeled only with LM 2. The hemicellulose B fraction, which is the main polysaccharide fraction from the pollen tube wall, reacted strongly with JIM 13 and especially LM 2, but not with antipectin antibodies. These results demonstrate that the wall constituents and their localization inP. densiflora pollen are considerably different from those reported in angiosperm pollen and suggest that the main components of the cell wall ofP. densiflora pollen are arabinogalactan and AGPs containing glucuronic acid.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 15
    ISSN: 1432-0878
    Keywords: Key words Hypophysis ; Aromatase ; Immunocytochemistry ; Morphometry ; Gender differences ; Rat (Sprague Dawley)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract In order to analyze whether aromatase is present in the hypophysis of adult rats, we have performed an immunohistochemical study in young adult male and female rats. Our study has revealed that the hypophysis of adult rats contains aromatase, although marked differences are found between the sexes. The hypophyses of male rats have cells immunoreactive for the enzyme, 34.40% of these hypophyseal cells showing reaction. By contrast, cells from female rats show very little reaction, only 0.84% of them being reactive. No significant differences in the percentage of immunoreactive cells between one phase and another are observed during the estrous cycle. Our results point to the immunohistochemical expression of aromatase in the hypophysis of adult rats and at the same time suggest that its expression is sex-dependent. The enzyme may therefore be involved in the regulation of adenohypophyseal cytology by androgens.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 16
    ISSN: 1432-2048
    Keywords: Key words:β-1 ; 3-Glucanase ; Immunocytochemistry ; Leaf rust pathogen ; Resistance ; Triticum (pathogen resistance)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract. An antiserum raised against the purified 33-kDa β-1,3-glucanase of wheat (Triticum aestivum L.) was employed to investigate the ultrastructural localization of the enzyme in wheat leaves infected with Puccinia recondita Rob. ex Desm. f.sp. tritici Eriks. and Henn. using a post-embedding immunogold labelling technique. In both compatible and incompatible interactions, β-1,3-glucanase was detected in the host plasmalemma and in the domain of the host cell wall near the plasmalemma of the mesophyll cells, but higher concentrations of the enzyme were detected in infected resistant wheat leaves than in infected susceptible ones. β-1,3-Glucanase was also found in the secondary thickening of xylem vessels and in the walls of guard cells, epidermal cells and phloem elements, while no labelling was observed in host organelles, viz. vacuoles, mitochondria, endoplasmic reticulum, Golgi bodies, nuclei and chloroplasts. A low concentration of the enzyme was detected on the intercellular hyphal wall and in the hyphal cytoplasm. In the compatible interaction, β-1,3-glucanase was demonstrated to accumulate predominantly in the haustorial wall and extrahaustorial matrix. In the incompatible interaction, strong labelling for β-1,3-glucanase was found in host cell wall appositions, in the extracellular matrix in the intercellular space, and in electron-dense structures of host origin which occurred in the incompatible interaction only.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 17
    ISSN: 1432-0878
    Keywords: Key words Pancreas ; exocrine ; Hibernation ; Amylase ; Immunocytochemistry ; Muscardinus avellanarius (Rodentia)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Pancreatic acinar cells of euthermic, hibernating and arousing individuals of the hazel dormouse Muscardinus avellanarius (Gliridae) have been observed at the electron-microscopic level and analysed by means of ultrastructural morphometry and immunocytochemistry in order to investigate possible fine structural changes of cellular components during periods of strikingly different degrees of metabolic activity. During hibernation, the cisternae of the rough endoplasmic reticulum (RER) flatten assuming a parallel pattern, the Golgi apparatus is extremely reduced and the mitochondria contain many electron-dense particles. The cell nuclei appear irregularly shaped, with deep indentations containing small zymogen granules. They also contain abundant coiled bodies and unusual constituents, such as amorphous bodies and dense granular bodies. Large numbers of zymogen granules occur in all animals. However, the acinar lumina are open and filled with zymogen only in euthermic animals, whereas, in hibernating and arousing individuals, they appear to be closed. Morphometrical analyses indicate that, in pancreatic acinar cells, nuclei and zymogen granules significantly decrease in size from euthermia to hibernation, probably reflecting a drastic decrease of metabolic activities, mainly protein synthesis and processing. In all the studied animals, immunocytochemistry with specific antibodies has revealed an increasing gradient in α-amylase content along the RER-Golgi-zymogen granule pathway, reflecting the protein concentration along the secretory pathway. Moreover, during deep hibernation, significantly larger amounts of α-amylase accumulate in RER and zymogen granules in comparison to the other seasonal phases analysed. Upon arousal, all cytoplasmic and nuclear constituents restore their euthermic aspect and all morphometrical and immunocytochemical parameters exhibit the euthermic values, thereby indicating a rapid resumption of metabolic activities.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 18
    ISSN: 1432-0878
    Keywords: Key words Adrenomedullin ; Pancreas ; Development ; Immunocytochemistry ; Colocalizations ; Rat (Sprague Dawley)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  Adrenomedullin is an α-amidated 52-amino acid peptide involved in many physiological actions, among others the regulation of insulin secretion. Using immunohistochemical methods, we found that adrenomedullin immunoreactivity first appears at day 11.5 of embryonic development in the rat, coinciding with the appearance of pancreatic glucagon. The early appearance of adrenomedullin in the developing pancreas may indicate an active involvement in either the morphogenesis of the organ or its endocrine/paracrine/autocrine hormone regulation during intrauterine life. We also investigated the pattern of colocalizations of adrenomedullin with the other pancreatic hormones. At some point during development all the cell types express adrenomedullin, progressively evolving towards the adult pattern where only the pancreatic polypeptide cells contain a strong immunoreactivity for adrenomedullin. At this point the remaining cells of the islet are, in general, weakly stained. This sequential and time-dependent expression of adrenomedullin suggests a tight regulation similar to that observed for other modulatory substances responsible for embryonic morphogenesis.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 19
    ISSN: 1432-0878
    Keywords: Key words Pepsinogen C ; Ontogeny ; Mucous neck cell ; Chief cell ; Intermediate mucopeptic cell ; Immunocytochemistry ; In situ hybridization ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  The ontogeny of pepsinogen C-producing cells in rat fundic glands was studied by means of light and electron microscopy using an antiserum raised against a synthetic peptide based on rat pepsinogen C. To confirm the immunocytochemistry results, the expression of rat pepsinogen C messenger RNA (mRNA) in the fundic gland was also examined by in situ hybridization using a digoxigenin-labeled RNA probe. In adult rats, pepsinogen C was produced by chief cells, mucous neck cells, and intermediate mucopeptic cells. Pepsinogen C-producing cells appeared in embryos as early as 18.5 days’ gestation. The development of these cells could be classified into four stages: (1) 18.5 days’ gestation to 0.5 days after birth; (2) 0.5 days to 2 weeks after birth; (3) 3–4 weeks after birth; (4) 4–8 weeks after birth. In embryos and young animals, pepsinogen C-producing cells were mucopeptic cells. By 4 weeks after birth, mucous neck cells could be distinguished morphologically. The maturation stages of the chief cells could be traced by electron microscopy along the longitudinal axis of the rat fundic gland by double-staining with anti-pepsinogen C antibody and periodic acid-thiocarbohydrazide-silver proteinate. Positive reactions for pepsinogen C and pepsinogen C mRNA expression were detected in mucous neck cells. Therefore, we conclude that mucous neck cells are precursor cells of chief cells. Mucous neck cells, intermediate cells, and chief cells are in the same differentiating cell lineage.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 20
    ISSN: 1432-0878
    Keywords: Key words Enteric nervous system ; Somatostatin ; Immunocytochemistry ; Intestinal motility ; Synaptic connections ; Guinea-pig
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  Somatostatin immunoreactivity occurs in a specific subgroup of cholinergic descending interneurons in the myenteric plexus of the guinea-pig small intestine. In the present work, we made light- and electron-microscopic investigations of chemically defined inputs to these neurons, in order that the origins of the connections of other neurons with them could be deduced. Somatostatin-immunoreactive synapses and close contacts were found on the cell bodies and filamentous processes of somatostatin neurons; these were 84% of all inputs. It is thus confirmed that this class of interneuron forms chains that project anally. Descending interneurons with immunoreactivity for nitric oxide synthase provided 14% of inputs to somatostatin-immunoreactive descending interneurons. An antiserum against a calcium-binding protein, calbindin, was used as marker for the majority of intrinsic primary afferent neurons, AH/Dogiel type II neurons; this class of neurons provided only 2.5% of the inputs to somatostatin-immunoreactive descending interneurons. We conclude that somatostatin-immunoreactive descending interneurons are involved in the conduction of impulses distally along the full length of the small intestine, but receive only a minor input from calbindin-immunoreactive primary afferent neurons.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 21
    ISSN: 1432-0878
    Keywords: Key words Annexin 5 ; Immunocytochemistry ; Pituitary ; Ovary ; Testis ; Adrenal gland ; Thyroid gland ; Rat (wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  Annexin 5, a unique calcium- and phospholipid-binding protein, has been investigated for its specific distribution in rat endocrine organs by immunocytochemistry with a specific antiserum to recombinant rat annexin 5. Follicular epithelial cells and parafollicular cells of the thyroid gland, adrenocortical cells of the zona fasciculata and zona reticularis, luteal cells, testicular interstitial cells, and Sertoli cells were shown to contain annexin 5. To examine whether the synthesis of annexin 5 would be affected by a change in humoral signal, the distribution of annexin 5 in the anterior pituitary was examined three weeks after ovariectomy. The withdrawal of ovarian hormones induced huge castration cells in the anterior pituitary gland, which contained abundant annexin 5. Annexin 5 was not detected in the pineal gland, the parathyroid gland, the islet of Langerhans, the adrenal medulla, zona glomerulosa cells, and granulosa cells. Since annexin 5 was shown to exist in many of the endocrine tissues examined, to be localized in specific cell types, and to be abundant in castration cells, it is suggested that annexin 5 contributes to secretory cell functions, which may be common to endocrine cells secreting chemically different hormones.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 22
    ISSN: 1432-0878
    Keywords: Key words Pancreas ; Stomach ; Duodenum ; Ribonuclease protection assay ; Immunocytochemistry ; Protease ; Rat ; (Sprague Dawley)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  Prior studies have revealed the presence of chymotrypsinlike protease in peripheral organs, although no definitive evidence for the synthesis of this enzyme in tissue other than the pancreas is available. In an attempt to detect chymotrypsinogen mRNA in peripheral organs, a fragment of the pancreatic chymotrypsin mRNA from rat was amplified using PCR. The sequence was identified as a portion of the rat chymotrypsin B gene overlapping exon 5 through exon 7. It was subcloned into the pGEM-4Z vector and used as a template for the vitro transcription of an antisense riboprobe. Using ribonuclease protection and Northern blot analyses, chymotrypsin mRNA was detected in the rat pancreas, stomach, duodenum, ovary, and spleen. Monoclonal and polyclonal antisera against chymotrypsin detected chymotrypsinlike immunoreactivity in rat and human pancreas, rat stomach, duodenum and jejunum. Electrophoresis and immunoblotting revealed chymotrypsin-chymotrypsinogen bands (25–29 kDa) in the stomach and duodenum. Synthesis of a potent protease such as chymotrypsin in tissue other than pancreas is significant, suggesting a potential physiological and/or pathological role in these tissues.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 23
    ISSN: 1432-0878
    Keywords: Key words Acrosome ; Epididymal maturation ; Monoclonal antibody ; Immunocytochemistry ; Spermatozoa ; Guinea pig
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  We have previously shown that a 90-kDa intra-acrosomal antigen, MN7, is restricted to the anterior acrosomal region of mouse, rat, and hamster spermatozoa. The present study has examined the localization and the behavior of MN7 during sperm maturation in the epididymis of the guinea pig by immunoelectron microscopy. MN7 showed not only a specific localization in the apical segment of the guinea pig sperm acrosome, but also a distinct alteration during maturation, as follows. MN7 was exclusively found both at the dorsal matrix and on the outer acrosome membrane (OAM)/matrix-associated materials in the apical segment. MN7 was initially distributed throughout the electron-lucent dorsal matrix in immature sperm but, during maturation, became more restricted to the spherical bodies within the electron-lucent area. MN7 on OAM/matrix-associated materials was first distributed along the ventral margin and the small area posterior to the dorsal matrix but, during maturation, disappeared from the ventral margin and became restricted to the dorsal region. These results indicate that MN7 is a good tool for studying the stepwise maturation of epididymal spermatozoa.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 24
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 293 (1998), S. 245-252 
    ISSN: 1432-0878
    Keywords: Key words Synaptic-like microvesicles ; Synaptophysin ; Synaptobrevin ; Immunocytochemistry ; Immunoelectron microscopy ; Meriones unguiculatus (Rodentia)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  Mammalian pinealocytes contain several synaptic membrane proteins which probably play a role in the targeting and exocytosis of secretory vesicles, in particular of synaptic-like microvesicles (SLMVs). The latter are considered as the endocrine equivalent of neuronal synaptic vesicles. By means of immunocytochemical techniques and immunoblot analyses, we now show that two further key components of the molecular apparatus regulating neurotransmitter release are present in the gerbil pineal gland, i.e., munc-18–1 and cysteine string protein (csp). In addition to varicosities of nerve fibres, munc-18–1 and csp could be localized to pinealocytes where both proteins were markedly enriched in process swellings. When using antibodies against csp for an immunogold electron-microscopic study of pinealocytes, gold particles consistently decorated profiles of pleomorphic SLMVs. Interestingly, we found that also the cytosolic protein munc-18, which is partially recruited to the plasmalemma in neurons, was associated to a significant extent with SLMVs of pinealocytes and synaptic vesicles of neurons, respectively. This localization implies that munc-18 at least partially exerts its regulatory functions while being bound to secretory vesicle membranes. Our results indicate that in endocrine cells such as pinealocytes the synaptic proteins munc-18–1 and csp play essential roles during the life cycle of SLMVs.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 25
    ISSN: 1432-0878
    Keywords: Key words Enamelin ; Immunocytochemistry ; Amelogenesis ; Tooth development ; Enamel ; Pig
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  Enamelins comprise an important family of the enamel matrix proteins. Porcine tooth germs were investigated immunochemically and immunocytochemically using two antibodies: a polyclonal antibody raised against the porcine 89-kDa enamelin (89 E) and an affinity purified anti-peptide antibody against the porcine enamelin amino-terminus (EN). Immunochemical analysis of layers of immature enamel from the matrix formation stage detected immunopositive protein bands ranging from 10 kDa to 155 kDa in the outer layer enamel sample irrespective of the antibodies used. In contrast, the middle and inner enamel layer mainly contained lower molecular weight enamelins. In immunocytochemical analyses of the differentiation stage, 89 E stained enamel matrix islands around mineralized collagen fibrils of dentin, while EN stained both enamel matrix islands and stippled material. At the matrix formation stage, both antibodies intensely stained enamel prisms located in the outer layer. In the inner layer, 89 E moderately stained enamel matrix homogeneously, while EN primarily stained the prism sheath. The intense immunoreaction over the surface layer of enamel matrix at the matrix formation stage, following staining with 89 E and EN, disappeared by the end of the transition stage and the early maturation stage, respectively. The Golgi apparatus and secretory granules in the ameloblasts from the late differentiation stage to the transition stage were immunostained by both antibodies. These results suggest that expression of enamelin continues from late differentiation to the transition stage and the cleavage of N-terminal region of enamelin occurs soon after secretion. Some enamelin degradation products, which apparently have no affinity for hydroxyapatite crystals, concentrate in the prism sheaths during enamel maturation.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 26
    ISSN: 1432-0878
    Keywords: Key words Salmon GnRH ; Chicken GnRH ; II ; Radioimmunoassay ; Immunocytochemistry ; In situ hybridization ; Oncorhynchus masou (Teleostei)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  Ontogenic development of salmon gonadotropin-releasing hormone (GnRH) and chicken GnRH-II systems in masu salmon (Oncorhynchus masou) was examined. Salmon GnRH was first detected by radioimmunoassay in the embryo on day 36 after fertilization. Salmon GnRH-immunoreactive fibers were detected initially by immunocytochemistry in the vicinity of the olfactory placode of the embryo (day 36) and were distributed widely in the brain as well as in the pituitary gland of fish just after hatching (day 80). Salmon GnRH-immunoreactive neuronal somata were first detected about 6 months after fertilization in the rostroventral brain area, ranging from the olfactory nerve to the preoptic area. Salmon GnRH neuronal somata were detected earlier by in situ hybridization than by immunocytochemistry. Neuronal somata expressing salmon GnRH mRNA were first detected in the vicinity of the olfactory epithelium on day 40 and then were seen to be migrating from the olfactory epithelium, along the olfactory nerve, on day 60 and in the transitional area between olfactory nerve and olfactory bulb on day 80. In the brain, these neurons were first detected in the ventral olfactory bulb on day 80, and thereafter they were also detected in the caudal brain regions. The chicken GnRH-II system was detected later than the salmon GnRH system; chicken GnRH-II was first detected by radioimmunoassay on day 57, and chicken GnRH-II-immunoreactive fibers were first detected on day 67. Chicken GnRH-II-immunoreactive neuronal somata were not detected during the observation period. These results suggest that salmon GnRH neurons derive from the olfactory placode and then migrate into the brain and that salmon GnRH is synthesized before chicken GnRH-II.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 27
    ISSN: 1432-0878
    Keywords: Key words Plant lectins ; Epithelial cells ; Immunocytochemistry ; Autoradiography ; Immunoelectron microscopy ; Potato leafhopper ; Empoasca fabae (Insecta)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract To identify the means by which phytohemagglutinin (PHA) exerts its toxicity on the potato leafhopper, four different methods (thick and semi-thin sectioning combined with immunofluorescent staining, in vitro receptor autoradiography, and immunoelectron microscopy) were used to elucidate the PHA target tissue, binding site, and its effects on this tissue. Sixteen 1- or 2-day-old female potato leafhoppers were fed for 36 h on each of three treatments: a control, diet or a diet containing either the PHA-E subunit or the PHA-L subunit. The PHA-E subunit, but not PHA-L, had previously been shown to be lethal. The insects were then prepared for both light and confocal microscopy. Analysis of images showed that PHA bound only to the surface of midgut epithelial cells of the potato leafhopper. PHA-E caused severe disruption, disorganization, and elongation of the brush border microvilli, and swelling of the epithelial cells into the lumen of the gut, leading to complete closure of the lumen. Furthermore, PHA-E stimulated the division of midgut epithelial cell nuclei, leading to two nuclei in each cell. Nuclei later elongated and degraded. In contrast, PHA-L had little effect on the epithelial cells of the midgut. It did not strongly bind to the surface of epithelial cells and caused much less disruption of brush-border microvilli, less disorganization of the cells and less elongation of nuclei. Strong binding of PHA occurred solely on the cell membrane of the brush border microvilli of epithelial cells. In contrast, the controls (i.e., midgut tissue, blocking agent, PHA, and antibodies) showed that midgut tissue was not autofluorescent and showed no fluorescent binding signal. Analysis of both bright- and dark-field images obtained by autoradiography and immunoelectron microscopy confirmed these findings.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 28
    ISSN: 1432-0878
    Keywords: Key words: Neurofilaments ; Phosphorylation ; Differentiation ; Immunocytochemistry ; Brain storage ; Fixation ; Microwave ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  Neurofilaments, which are exclusively found in nerve cells, are one of the earliest recognizable features of the maturing nervous system. The differential distribution of neurofilament proteins in varying degrees of phosphorylation within a neuron provides the possibility of selectively demonstrating either somata and dendrites or axons. Non-phosphorylated neurofilaments typical of somata and dendrites can be visualized with the aid of monoclonal antibody SMI 311, whereas antibody SMI 312 is directed against highly phosphorylated axonal epitopes of neurofilaments. The maturation of neuronal types, the development of area-specific axonal networks, and the gradients of maturation can thus be demonstrated. Optimal immunostaining with SMI 311 and SMI 312 is achieved when specimens are fixed in a mixture of paraformaldehyde and picric acid for up to 3 days and sections are incubated free-floating. Neurons, with their dendritic domains immunostained by SMI 311 in a Golgi-like manner, can be completely visualized in relatively thick sections. The limitations of Golgi-preparations, such as glia-labeling, artifacts, and the staining of only a small non-representative percentage of existing neurons, are not apparent in SMI preparations, which additionally provide the possibility of selectively staining axonal networks. The results achieved in normal fetal brain provide the basis for studies of developmental disturbances.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 29
    ISSN: 1432-0878
    Keywords: Key words Co-expression of mRNAs ; Gonadotropin-releasing hormone ; Immunocytochemistry ; In situ hybridization ; Oncorhynchus nerka (Teleostei)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  The localization of two salmon-type gonadotropin-releasing hormone (sGnRH) precursors, pro-sGnRH-I (short type) and pro-sGnRH-II (long type), was investigated by using in situ hybridization techniques in the brain of the landlocked sockeye salmon, Oncorhynchus nerka. We used 30-mer oligonucleotide probes complementary to pro-sGnRH-I and pro-sGnRH-II cDNA. No significant differences were observed in the localization of sGnRH neurons expressing pro-sGnRH-I and pro-sGnRH-II mRNAs; both were expressed in the olfactory nerve, the olfactory bulbs, the regions between the olfactory bulb and telencephalon, the ventral telencephalon, the preoptic area, and the hypothalamus. Almost all sGnRH neurons examined co-expressed both precursors. The expression of two sGnRH precursors in the same neuron and the wide distribution of such neurons in the brain suggest that there are no functional differences between the two precursors.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 30
    ISSN: 1432-0878
    Keywords: Key words Fish ; Zebrafish ; Immunocytochemistry ; Keratin ; Cytoskeleton ; Danio rerio (Teleostei)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  We have identified a number of type I and type II keratins in the zebrafish Danio rerio by two-dimensional polyacrylamide gel electrophoresis, complementary keratin blot-binding assay and immunoblotting. These keratins range from 56 kDa to 46 kDa in molecular mass and from pH 6.6 to pH 5.2 in isoelectric point. Type II zebrafish keratins exhibit significantly higher molecular masses (56–52 kDa) compared with the type I keratins (50–48 kDa), but the isoelectric points show no significant difference between the two keratin subclasses (type II: pH 6.0–5.5; type I: pH 6.1–5.2). According to their occurrence in various zebrafish tissues, the identified keratins can be classified into “E” (epidermal) and “S” (simple epithelial) proteins. A panel of monoclonal anti-keratin antibodies has been used for immunoblotting of zebrafish cytoskeletal preparations and immunofluorescence microscopy of frozen tissue sections. These antibodies have revealed differential cytoplasmic expression of keratins; this not only includes epithelia, but also a variety of mesenchymally derived cells and tissues. Thus, previously detected fundamental differences in keratin expression patterns between higher vertebrates and a salmonid, the rainbow trout Oncorhynchus mykiss, also apply between vertebrates and the zebrafish, a cyprinid. However, in spite of notable similarities, trout and zebrafish keratins differ from each other in many details. The present data provide a firm basis from which the application of keratins as cell differentiation markers in the well-established genetic model organism, the zebrafish, can be developed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 31
    ISSN: 1432-0878
    Keywords: Key words Electron microscopy ; F-actin ; Freeze-fracture ; Immunocytochemistry ; Water permeability ; Antidiuretic hormone ; Urinary bladder ; Rana temporaria (Anura)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  Electron and confocal microscopy, using immunocytochemical methods, was employed to assess osmotic water permeability of the frog (Rana temporaria) urinary bladder during transcellular water transport, induced by antidiuretic hormone (ADH) or by wash-out of autacoids from serosal, ADH-free Ringer solution. The increase of osmotic water permeability of the urinary bladder was accompanied by relevant ultrastructural changes, the most remarkable being: (1) the appearance of aggregates of intramembranous particles in the apical membrane of granular cells, and the extent of the membrane area covered by the aggregates proportional to that of the water flow; (2) redistribution of actin filaments in the cytoplasm of granular cells; judging from the anti-actin label density, the number of actin filaments in the apical region of cytoplasm was reduced by 2.5–4 times compared with normal; (3) a decrease in the total electron density of the cytoplasm due to the increased water content of granular cells.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 32
    ISSN: 1432-0878
    Keywords: Key words Mammalian-type thyrotropin ; Pituitary ; Immunocytochemistry ; Australian lungfish ; Neoceratodus forsteri (Dipnoi)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The binding sites of polyclonal antisera raised against the β-subunit of human thyroid-stimulating hormone (hTSHβ), hTSH, and ovine TSH (oTSH) have been localized in the pituitary gland of the Australian lungfish, Neoceratodus forsteri, using light microscopy. Reactivity toward anti-TSH antiserum was demonstrated in a slightly elongated and irregularly-shaped distinct cell type forming clusters in the dorso-central and ventral regions of the distal lobe. Their granules react with alcian blue (AB), and with periodic acid–Schiff (PAS), and after AB-PAS-orange G they stain blue or purple. The specificity of the different antisera was established by liquid-phase absorptions and confirmed in positive and negative tissue control systems. Our observations confirm that dipnoan (Neoceratodus) TSH shares a number of antigenic determinants with those of mammalian TSHβ and support the concept that mammalian TSHβ, or part of it, was established early in evolution, and that dipnoans (Neoceratodus) as living sarcopterygians may have an ancestor in common with the early amphibians. The mapping and detailed description of TSH-like immunoreactive cells may furnish a background to facilitate current and future analysis of the ontogeny and time course of TSH production and release in Neoceratodus in relation to different physiological conditions.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 33
    ISSN: 1615-6102
    Keywords: Chloroplast development ; Cotton ; Fluorescence induction kinetics ; Ultrastructure ; Immunocytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Many of the studies of chloroplast ontogeny in higher plants have utilized suboptimal conditions of light and growth to assess development. In this study, we utilized structural, immunological, and physiological techniques to examine the development of the chloroplast in fieldgrown cotton (Gossypium hirsutum cv. “MD 51 ne”). Our youngest leaf sample developmentally was completely folded upon itself and about 0.5 cm in length; leaves of this same plastochron were followed for three weeks to the fully expanded leaf. The chloroplasts at the earliest stage monitored had almost all of the lamellae in small, relatively electron-opaque grana, with relatively few thylakoids which were not appressed on at least one surface. During the development of the thylakoids, the membranes increase in complexity, with considerable stroma lamellae development and an increase in the number of thylakoids per granum. Besides the increase in complexity, both the size and numbers of the chloroplast increase during the development of the leaf. Developmental changes in six thylakoid proteins, five stromal proteins, and one peroxisomal protein were monitored by quantitative immunocytochemistry. Even at the earliest stages of development, the plastids are equipped with the proteins required to carry out both light and dark reactions of photosynthesis. Several of the proteins follow three phases of accumulation: a relatively high density at early stages, a linear increase to keep step with chloroplast growth, and a final accumulation in the mature chloroplast. Photosystem-II(PS II)-related proteins are present at their highest densities early in development, with an accumulation of other parts of the photosynthetic apparatus at a latter stage. The early accumulation of PS-II-related proteins correlates with the much lower ratio of chlorophylla tob in the younger leaves and with the changes in fluorescence transients. These data indicate that some of the conclusions on chloroplast development based upon studies of intercalary meristems of monocots or the greening of etiolated plants may not be adequate to explain development of chloroplasts in leaves from apical meristems grown under natural conditions.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 34
    ISSN: 1615-6102
    Keywords: Ferritin ; Nitrogen fixation ; Nodule development ; Plastid ; Legume ; Immunocytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary In eukaryotic organisms ferritin is a protein involved in the storage of iron. The occurrence of ferritin and its relationship to the effectiveness of the nitrogen-fixing activity have been previously studied during the early stages of the nodule development by biochemical methods. We have used immunocytochemistry techniques to determine the precise location of ferritin and the behavior of this protein along the nodule development. The major localization was found in plastids and amyloplasts of infected and uninfected cells of the three legume nodules studied. A decrease of the immunolabelling was observed in infected cells of lupin and soybean senescing nodules and in the senescent zone of indeterminate alfalfa nodules. In the cortex of soybean and lupin nodules, ferritin increased during nodule ageing and the immunogold particles were mainly located in crystalline structures. The putative role of ferritin and plastids during nodule development is discussed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 35
    ISSN: 1615-6102
    Keywords: Lupinus albus ; Nitrogen fixation ; Oxygen diffusion ; Glycoprotein ; Immunocytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The monoclonal antibodies MAC236 and MAC265, raised against a soluble component of pea nodules, were used to elucidate the presence and subcellular localization of glycoprotein epitopes during the development of lupin (Lupinus albus L. cv. Multolupa) nodules, by means of immunocytochemistry and Western blot analysis. These antibodies recognize a single band of 95 kDa in pea, soybean and bean nodules, whilst two different bands of 240 and 135 kDa cross-react with MAC236 and MAC265 respectively in lupin nodules. This fact may indicate that the recognized epitopes can be present in different subcellular compartments and/or play different roles through the development of functional nodules. The results show that MAC265 is mainly associated with Bradyrhizobium infection and with the development of nodule primordium, in the first stages of nodulation. MAC265 is also detected when glycoprotein transport takes place across the cytoplasm and the cell wall, and also in the intercellular spaces of the middle cortex, attached to cell walls. The amount of MAC265 remains constant through nodule development. In contrast the amount of MAC236 increases with nodule age, parallel to the establishment of nitrogenase activity. This antibody is localized in cytoplasmic globules attached to the inner side of cell walls in the middle cortex, and mainly in the matrix filling the intercellular spaces of the middle and inner cortex. This main site of localization of MAC236 may indicate a role in the functioning of the oxygen diffusion barrier.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 36
    ISSN: 1615-6102
    Keywords: Flax ; Cell wall ; Golgi apparatus ; β-Galactans ; Immunocytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Most cell wall components are carbohydrate including the major matrix polysaccharides, pectins and hemicelluloses, and the arabinogalactan-protein proteoglycans. Both types of molecules are assembled in the Golgi apparatus and transported in secretory vesicles to the cell surface. We have employed antibodies specific to β-(1→6) and β-(1→4)-D-galactans, present in plant cell wall polysaccharides, in conjunction with immunofluorescence and electron microscopy to determine the location of the galactan-containing components in the cell wall and Golgi stacks of flax root tip tissues. Immunofluorescence data show that β-(1→4)-D-galactan epitopes are restricted to peripheral cells of the root cap. These epitopes are not expressed in meristematic and columella cells. In contrast, β-(1→6)-D-galactan epitopes are found in all cell types of flax roots. Immunogold labeling experiments show that both epitopes are specifically located within the wall immediately adjacent to the plasma membrane. They are also detected in Golgi cisternae and secretory vesicles, which indicates the involvement of the Golgi apparatus in their synthesis and transport. These findings demonstrate that the synthesis and localization of β-(1→4)-D-galactan epitopes are highly regulated in developing flax roots and that different β-linked D-galactans associated with cell wall polysaccharides are expressed in a cell type-specific manner.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 37
    ISSN: 1432-0878
    Keywords: Key words Histamine ; Immunocytochemistry ; Mast cells ; Melanocytes ; Nerves ; Rana esculenta (Anura)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  The number, distribution, and ultrastructural characteristics of mast cells were assessed in the tongue, heart, and kidney of the frog Rana esculenta. The density of tongue mast cells (253±45 mast cells/mm2) was significantly higher than that of the heart (5.3±0.4/mm2) and kidney (15.3±1.4 /mm2). A striking feature of this study was the remarkable association of frog mast cells to nerves. The ultrastructural study of the mast cell/nerve association demonstrated that mast cells were closely apposed to or even embedded in nerves. Mast cells were also physically associated with melanocytes even in the heart. Mast cells were Alcian blue+/safranin+ in the tongue and in the peritoneum, whereas in the heart and in the kidney they were Alcian blue–/safranin+. The mast cells in the lamina propria of the gastrointestinal tract were Alcian blue+/safranin–. The cytoplasm of frog mast cells was packed with numerous heterogeneous, membrane-bound granules. The ultrastructure of these cytoplasmic granules was unique, being totally unlike any other previously described granules in other animal species as well as in man. The histamine content/frog mast cell (≈0.1 pg/cell) was approximately 30 times lower than that of human mast cells isolated from different tissues (≈3 pg/cell). A monoclonal anti-histamine antibody was used to confirm the ultrastructural localization of histamine in secretory granules in frog mast cells.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 38
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 293 (1998), S. 349-355 
    ISSN: 1432-0878
    Keywords: Key words Germ cells ; Nucleus ; Ribonucleoproteins ; Immunocytochemistry ; Rabbit
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  The convoluted cords present in the nuclei of rabbit primary spermatocytes and spermatids differ from previously described nuclear bodies. They are composed of proteic strands decorated with granules and, in most cases, are embedded in clusters of interchromatin granules. They are partly sensitive to trypsin and can be visualised with protein-specific stains. The decorating granules are similar in size and aspect to interchromatin granules. However, only the latter are continuously immunolabelled with anti-snRNPs (small ribonucleoproteins) antibodies during spermatogenesis. The complexity and organisation of the convoluted cords are modified specifically during cell differentiation. They might be involved in the storage, transport and release of interchromatin granules in male germ cells.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 39
    ISSN: 1432-0878
    Keywords: Key words Insect nervous system ; Immunocytochemistry ; Neural development ; Neuropeptide ; Neurohormone ; Locustatachykinin ; Spodoptera litura (Insecta)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  Neuropeptides with similarities to vertebrate tachykinins, designated tachykinin-related peptides (TRPs), have been identified in several insect species. In this investigation we have utilized an antiserum raised to one of the locust TRPs, locustatachykinin-I (LomTK-I), to determine the distribution pattern of LomTK-like immunoreactive (LTKLI) neurons in the developing nervous system of the moth Spodoptera litura. A number of LTKLI neurons could be followed from the larval to the adult nervous system: a set of median neurosecretory cells (MNCs) in the brain, a pair of brain descending neurons and a few sets on neurons in the ventral nerve cord. The distribution of LTKLI neurons in the adult brain is very similar to that seen in other insect species with prominent arborizations in the central body, antennal lobes, mushroom body calyces, optic lobe neuropils and other distinct neuropil areas in the protocerebrum and tritocerebrum. A new finding is the presence of LTKLI neurosecretory cells with axon terminals in the anterior aorta and corpora cardiaca, suggesting for the first time a neurohormonal role of tachykinin-related peptide(s) in insects. During postembryonic development the number of LTKLI neurons in the ventral nerve cord decreases somewhat, whereas the number increases in the brain. Thus the functional roles of TRPs may change to some extent during development.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 40
    ISSN: 1432-0878
    Keywords: Key words: Urothelium ; Tartrate-resistant acid phosphatase ; Nitric oxide synthase I ; Superoxide dismutase ; Immunocytochemistry ; Free radicals ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. Three enzymes, viz., tartrate-resistant acid phosphatase (TRAP), nitric oxide synthase I (NOS-I), and superoxide dismutase (SOD), involved in the production and metabolism of free radicals or radical equivalents, were demonstrated by immunocytochemistry in the urothelium of the ureters of six patients of various ages. Two of these enzymes (TRAP and NOS-I) were colocalized in the most apical and lateral border of the superficial cells of the urothelium. In contrast, SOD showed a patchy or granular distribution within the supranuclear region of these cells. Intra- and subepithelial macrophages exhibited a weak TRAP, but no NOS-I or SOD, immune reaction. On the basis of the immunocytochemical findings, arguments in favor of a cytotoxic function of the superficial cells of the human urothelium are presented.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 41
    ISSN: 1432-0878
    Keywords: Key words: Arginine ; Analogues ; Immunocytochemistry ; Nitric oxide ; Pituitary ; Retina ; Transport ; Rat (Wistar) ; Rabbit
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. Nitric oxide is formed by the action of nitric oxide synthase upon l-arginine. The efficacy of some exogenously applied arginine analogues in inhibiting nitric oxide synthase and thus nitrergic transmission indicates that neurons producing nitric oxide may possess an arginine transport system. To investigate whether arginine analogues are preferentially transported into nitric oxide-utilising cells or into cells making other neurochemicals, we have raised highly specific antisera against a number of arginine analogues including NG-methyl arginine, d-arginine, NGnitro-l-arginine, NG-nitro-l-arginine methyl ester and canavanine. Retinae were incubated in physiological media containing these analogues and rats were given intraperitoneal injections of the analogues to study the pituitary. Immunocytochemistry and NADPH-diaphorase histochemistry revealed that many of these analogues could be transported preferentially, but not exclusively, into nitric oxide-generating cells. However, some nitric oxide-producing cells apparently lacked the ability to take up some arginine analogues. We conclude that nitric oxide-generating cells in the retina and pituitary possess one or more arginine transporters. Other subsets of neurons that use GABA or glutamate as a neurotransmitter may also accumulate arginine analogues, possibly as a substrate for formation of these neurochemicals.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 42
    ISSN: 1432-0878
    Keywords: Key words: Crustacean hyperglycaemic hormone ; Immunocytochemistry ; Neurohaemal organ ; Daphnia magna ; Artemia salina (Crustacea)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. Crustacean hyperglycaemic hormone-immunoreactive neuronal systems are detected in the central and peripheral nervous systems of two entomostracan crustaceans, Daphnia magna and Artemia salina, by immunocytochemistry using specific antisera against crustacean hyperglycaemic hormones of the decapod crustaceans Orconectes limosus and Carcinus maenas. In D. magna, four small putative interneurones are detected in the brain. In the thorax, ten bipolar peripheral neurones are stained by both antisera. They are obviously segmental homologues with centrally projecting axons that form interdigitating varicose fibres and terminals in putative neurohaemal areas next to the surface of the anterior part of the thoracic ganglia. Similar immunopositive neurones occur both in the central and peripheral nervous systems of A. salina. A total of five groups of neurones occur in the protocerebrum, the deutocerebrum and the mandibular ganglion. Some of the protocerebral neurones are bipolar and project to the dorsal frontal organ. A single pair of peripheral multipolar neurones in the maxillary segment projects centrally into the ventral nerve cord and innervates unidentified somatic muscles and tissues in the maxillary and the first appendage segments. None of the brain neurones in both species show similarities to decapod X-organ sinus gland neurosecretory neurones. Chromatography of brain extracts of D. magna combined with immunodot blotting revealed two strongly immunoreactive fractions at retention times close to that of the crustacean hyperglycaemic hormone of crayfish. Moreover, preabsorption controls suggest that the cross-reacting peptides of D. magna and A. salina are structurally closely related to those of decapods.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 43
    ISSN: 1432-0878
    Keywords: Key words: Apoptosis ; Neuronal plasticity ; Hypothalamus ; Astrocytes ; Immunocytochemistry ; Western blot ; Rat (Sprague Dawley)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. A polyclonal antibody raised against a peptide corresponding to the (2–19) amino-terminal sequence of the Bcl-xL/S protein was used to localize Bcl-x immunostaining in the central nervous system of rats at various postnatal ages. Whereas Bcl-x immunostaining was present in virtually all neurons of young animals (4 days postnatal), this staining became progressively restricted during the course of postnatal development. In adults, Bcl-x immunostaining was particularly strong in certain neurons present in a few hypothalamic nuclei, such as the supraoptic or the arcuate nuclei. Moderate staining was observed in some discrete brain regions, such as the olfactory bulb, the hippocampus, some catecholaminergic nuclei of the brainstem, and the cerebellum. Strong Bcl-x immunostaining was also exhibited in axon-like fibers located in the pyriform cortex, the median eminence, the dorsal medulla oblongata, and spinal cord. Bcl-x immunostaining was also present in astrocytes scattered throughout the white matter in the brain and the spinal cord, but was absent from those located in gray matter. Staining was particularly strongly expressed in reactive astrocytes densely packed along the borders of a central lesion or surrounding them, and in a large number of reactive astrocytes detected at a distance from the lesion. Our data suggest that, in addition to the possible stimulating effects on cell survival generally ascribed to Bcl-x, its maintained expression throughout adulthood or its re-expression following injury characterizes those neuronal or non-neuronal cells of the adult central nervous system that synthesize a range of molecules enabling them to adapt rapidly and successfully to a changing environment.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 44
    ISSN: 1432-0878
    Keywords: Key words: FMRFamide ; Immunocytochemistry ; Central nervous system ; Lumbricus terrestris (Annelida)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. The distribution of FMRFamide-like immunoreactive cell bodies and fibers in the nervous system of the earthworm Lumbricus terrestris has been studied by means of immunocytochemistry. The cerebral ganglion contains 150–170 immunoreactive nerve cells that are organized into six major groups in the rostral and five major groups in the caudal part of the ganglion; 160–180 immunoreactive nerve cells are present in the subesophageal ganglion, and 80–90 in the ventral cord ganglia. Immunoreactive neurons of the subesophageal and the ventral cord ganglia show similar distributions, in that FMRFamide-like immunoreactive cells form a ventromedial and a lateral cell group. Neuropil in all parts of the central nervous system shows intensively stained varicose and non-varicose fibers. Each segmental nerve contains FMRFamide-like immunoreactive fibers that can partly be traced to the two muscle layers of the body wall, and a fine immunoreactive network lies among the muscle fibers. A similar network is found in the wall of the alimentary canal. Immunopositive perikarya and fibers have been detected in the prostomial nerves, in the stomatogastric system. Some epithelial cells of the body wall are also immunopositive. The morphological characteristics and localization of FMRFamide immunoreactive neurons suggest that they may be involved in: (1) central integratory processes; (2) neuromuscular regulation in both the body wall and enteric system; (3) sensory processes.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 45
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 289 (1997), S. 265-274 
    ISSN: 1432-0878
    Keywords: Key words: Retina ; Amacrine cells ; Neurotransmitters ; Immunocytochemistry ; Tyrosine hydroxylase ; Dopamine ; Ichthyophis kohtaoensis (Gymnophiona)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. Ichthyophis kohtaoensis, a member of the limbless Gymnophiona, has a specialized subterranean burrowing mode of life and a predominantly olfactory-guided orientation. The only visually guided behavior seems to be negative phototaxis. As these animals possess extremely small eyes (only 540 μm in diameter in adults), functional investigations of single retinal cells by electrophysiological methods have so far failed. Therefore, the content and distribution of retinal transmitters have been investigated as indications for a functioning sense organ in an animal that is supposed to be blind. In this study, the organization and development of the dopaminergic system have been examined in the retinae of embryonic, larval, and adult I. kohtaoensis, by using an antiserum against tyrosine hydroxylase, the rate-limiting enzyme in the catecholamine synthetic pathway, and an antiserum against dopamine itself. Labeled somata are situated in the inner nuclear layer and in the ganglion cell layer. Dopamine-positive fibers form a dense diffuse plexus, that covers the whole inner plexiform layer, whereas tyrosine hydroxylase-immunoreactive processes show a tendency to arborize in a stratified manner. Tyrosine-hydroxylase-immunolabeled fibers can occasionally be observed in the optic nerve head of larval stages. During ontogenesis and larval development, the distribution of transmitter-expressing cells changes and their number decreases, but no general degeneration of the visual system is detectable. Adult Ichthyophis still have retinal transmitters, indicating that the eyes, although obviously playing a minor role in a subterranean ecological niche, retain all the elements of functioning sense organs.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 46
    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
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 47
    ISSN: 1432-0878
    Keywords: Key words Estrogen receptor ; Progesterone receptor ; Gonadotropin-releasing hormone ; Preoptic area ; Hypothalamus ; Immunocytochemistry ; Mink (Mustela vison)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  The distribution of gonadal steroid (estrogen, progesterone) receptors in the brain of the adult female mink was mapped by immunocytochemistry. Using a monoclonal rat antibody raised against human estrogen receptor (ER), the most dense collections of ER-immunoreactive (IR) cells were found in the preoptic/anterior hypothalamic area, the mediobasal hypothalamus (arcuate and ventromedial nuclei), and the limbic nuclei (amygdala, bed nucleus of the stria terminalis, lateral septum). Immunoreactivity was mainly observed in the cell nucleus and a marked heterogeneity of staining appeared from one region to another. A monoclonal mouse antibody raised against rabbit uterine progesterone receptor (PR) was used to identify the PR-IR cells in the preoptic/anterior hypothalamic area and the mediobasal hypothalamus (arcuate and ventromedial nuclei). This study also focused on the relationship between cells containing sex-steroid receptors and gonadotropin-releasing hormone (GnRH) neurons on the same sections of the mink brain using a sequential double-staining immunocytochemistry procedure. Although preoptic and hypothalamic GnRH neurons were frequently in close proximity to perikarya containing ER or PR, they did not themselves possess receptor immunoreactivity. The present study provides neuroanatomical evidence that GnRH cells are not the major direct targets for gonadal steroids and confirms for the first time in mustelids the results previously obtained in other mammalian species.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 48
    ISSN: 1432-0878
    Keywords: Key words Immunochemistry ; Chromatography ; Immunocytochemistry ; PACAP ; VIP ; CGRP ; NOS ; GRP ; Gastointestinal tract ; Capsaicin ; Denervation ; Rat (Sprague Dawley ; Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  The expression of pituitary adenylate cyclase activating polypeptide (PACAP) was studied in the gastrointestinal tract (GI-tract) of normal rats using radioimmunoassay, chromatography, immunocytochemistry, and in situ hybridization. PACAP-38, PACAP-27, and PACAP-related peptide were demonstrated in all parts of the GI-tract, PACAP-38 being the predominant form confirmed by chromatography. PACAP-immunoreactive nerve fibers and nerve cell bodies were found in the myenteric ganglia throughout the GI-tract. PACAP-containing nerve cell bodies were also demonstrated in the submucous ganglia of the small and large intestine. The synthesis of PACAP in intrinsic neurons was confirmed by in situ hybridization. Double immunostaining showed that PACAP is present in calcitonin gene-related peptide-containing sensory nerve fibers as well as in vasoactive intestinal polypeptide (VIP)- or VIP/gastrin-releasing peptide (GRP)-containing (intramural) nerve fibers in the upper GI-tract and in anally projecting, intrinsic VIP-and VIP/nitric oxide syntase-containing nerve cell bodies and nerve fibers in the small and large intestine. Neonatal treatment with capsaicin significantly reduced the concentration of PACAP-38 in the esophagus, stomach, and colon. Extrinsic denervation decreased the PACAP-38 concentration in the stomach, while no change was observed in the small intestine. These results indicate that PACAP- immunoreactive nerve fibers in the GI-tract originate from both intrinsic (enteric) and extrinsic (presumably sensory) sources suggesting that PACAP may have diverse gastrointestinal functions.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 49
    ISSN: 1432-0878
    Keywords: Key words: Allatostatin ; Immunocytochemistry ; In situ hybridization ; Hemocytes ; Inhibition of corpora allata ; Diploptera punctata (Insecta)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. Allatostatins are neuropeptides that inhibit the production, by the corpora allata, of a major insect hormone, juvenile hormone. These peptides are produced by cells of the brain and ganglia as well as by midgut endocrine cells. Transport from these sites may contribute to the allatostatin content in the hemolymph (insect blood). Using a monoclonal antibody against Diploptera punctata allatostatin I (A-P-S-G-A-Q-R-L-Y-G-F-G-L-NH2) and in situ hybridization with a digoxigenin-labeled cRNA probe generated from a portion of the allatostatin gene, it is demonstrated that allatostatin is present in and synthesized by granular hemocytes of D. punctata. About 5% of the hemocytes react with anti-allatostatin antibody and a similar number hybridize with a cRNA probe that detects allatostatin-specific mRNA. Electron micrographs showed that allatostatin-immunoreactive material occurs in membrane-bound, uniformly dense granules that frequently fill fusiform-shaped cells. Allatostatin in cell and plasma fractions of hemolymph quantified by enzyme-linked immunosorbent assay and by bioassay for inhibition of juvenile hormone synthesis in vitro indicated that about equal quantities (0.1–0.2 fmol/μl) are present in cell and plasma fractions. The production of allatostatin by hemocytes suggests that allatostatins may function as regulatory peptides in hemolymph activities in addition to their other known functions.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 50
    ISSN: 1432-0878
    Keywords: Key words: Aquaporins ; AQPcic ; Filter chamber ; Homopteran insects ; Immunocytochemistry ; Cicadella viridis ; Euscelidius variegatus ; Scaphoideus titanus (Insecta)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. In the Homopteran order of insects, the plant xylem feeders exhibit a highly differentiated part of their digestive tract known as the filter chamber. In this tissue, water crosses plasma membranes through a transepithelial osmotic gradient. In previous studies on the filter chamber of Cicadella viridis, we purified and characterized from the plasma membranes a 25 kDa protein that we demonstrated to be an aquaporin (or water channel, member of the major intrinsic protein family, a group of membrane channels for small solutes). We called this protein AQPcic for Cicadella aquaporin. In the present study, we used polyclonal antibody anti-AQPcic in Western blotting and immunocytochemical analysis of the intestinal tract of Cercopis sanguinolenta, Philaenus spumarius, Aphrophora alni (Cercopidae), Euscelidius variegatus, and Scaphoideus titanus (Jassidae). Western blotting experiments revealed that immunologically related AQPcic proteins are found in those species. The molecular weight of these proteins is 15–26 kDa. Immunocytochemical studies on ultrathin filter-chamber sections revealed that the anti-AQPcic antibody systematically labelled the membrane microvilli of epithelial cells. A good correlation thus exists between the physiology of these cells and the presence of aquaporin-related proteins in their membranes.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 51
    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
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 52
    ISSN: 1432-0878
    Keywords: Key words: Oxytocin ; Immunocytochemistry ; Paraventricular nucleus ; Superior cervical ganglion ; Spinal cord ; Sympathetic nervous system ; Retrograde tracing ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. The paraventricular nucleus of the hypothalamus is a major integrative nucleus for relaying information from the suprachiasmatic nucleus to the autonomic system. The precise pathway by which this information can influence autonomic functions, such as melatonin synthesis in the pineal gland, is not clear. In the present study, we used a retrograde tracer injected in the superior cervical ganglion to identify spinal preganglionic neurons. One of the main neurotransmitters present in descending projections of the paraventricular nucleus of the hypothalamus, oxytocin, was detected with immunocytochemistry to visualise possible contacts with the neurons located in the intermediolateral column of the spinal cord and projecting to the superior cervical ganglion. Although many appositions could be seen at the light-microscopic level, this abundance could not be confirmed at the electron-microscopic level. The implications of these observations for the overall timing message received by the spinal preganglionic neurons are discussed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 53
    ISSN: 1432-0878
    Keywords: Key words: NPY ; VIP ; Pelvic ganglia ; Immunocytochemistry ; In situ hybridization ; Retrograde tracing (Fluoro-Gold) ; Genital tract ; Rat (Sprague Dawley)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. The present study investigates the distribution and coexpression of neuropeptide Y (NPY) and vasoactive intestinal peptide (VIP) in neurones of the accessory ganglion (AG), hypogastric plexus (HP) and paracervical ganglion (PCG), which compose the pelvic plexus in the female rat. Nerve cell bodies immunoreactive for NPY and VIP represent 84% and 46% of the neurone population in the PCG, respectively, while immunoreactivity for each peptide is observed in about 90% of the AG and HP neurones. Adjacent sections immunostained for NPY and VIP, as well as the use of immunocytochemistry combined with in situ hybridization show that 92% of the VIP-containing neurones in the pelvic plexus also contain NPY. In addition, a retrograde tracing study performed in combination with immunocytochemistry demonstrates that pelvic plexus neurones project preferentially to the lower part of the uterus and to the cervix, and that about 95% of these projecting neurones contain VIP. Taken together, our findings indicate that in the female rat, neurones of the pelvic plexus projecting to the lower genital tract mainly coexpress VIP and NPY, and supply nerve fibres to the vascular and nonvascular smooth muscle in the uterocervical region. Since NPY and VIP exert distinct effects according to the target tissue, our results suggest that neurones coexpressing these peptides play important roles in the local regulation of the vascular bed and motor activity of the lower genital tract.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 54
    ISSN: 1432-0878
    Keywords: Key words: Pineal organ ; Pinealocytes ; Pineal photoreceptors ; Sensory structures ; Photopigment ; Pinopsin ; Immunocytochemistry ; Chicken
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. Pinopsin is a photoreceptive molecule cloned from the chicken pineal organ. An antibody highly specific for pinopsin was applied in light- and electron-microscopic immunocytochemical studies of the pineal organ of 1 to 2-month-old chickens. Intense immunoreactivity was found in the follicular lumen at the light-microscopic level. In addition, small immunoreactive spherical or fibrous structures were diffusely distributed at the parafollicular aspect of the pineal organ. To identify immunoreactive elements precisely, we used pre-embedding immunoelectron microscopy. These studies revealed immunoreactive outer segments of pinealocytes arranged closely side by side in the follicular lumina. The thin initial portion of the outer segment arose from a basal body located in the inner segment. Immunoreactive pear-shaped outer segments occupied small lumina. Follicular lumina displayed immunonegative arrays of whorl-like lamellar membranes. Occasionally, these immunonegative structures were surrounded by immunoreactive concentric lamellar complexes. In the parafollicular pineal parenchyma, long slender cilium-like structures or enlarged cilia and concentric lamellar arrays showed intense immunoreactivity. All immunoreactive structures observed in this study were considered to represent outer segments of pinealocytes of the chicken pineal organ.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 55
    Electronic Resource
    Electronic Resource
    Springer
    Protoplasma 198 (1997), S. 130-134 
    ISSN: 1615-6102
    Keywords: Casuarina ; Frankia ; Nodules ; Nitrogen-fixation ; Hemoglobin ; Immunocytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Immunocytochemical localisation of hemoglobin on sections ofFrankia-infecledCasuarina glauca nodule tissue confirmed its presence in nitrogen-fixing infected cells. Using colloidal gold as the marker, hemoglobin was shown to be restricted to the cytoplasm and nucleus of infected cells. None was associated with endophyte hyphae or uninfected cells. As infection developed, with its associated thickening and modification of host cell walls, the level of label, and by implication, the level of hemoglobin increased.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 56
    ISSN: 1615-6102
    Keywords: Apical growth ; Brefeldin A ; Immunocytochemistry ; Fungus ; Golgi body
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Candida albicans, a dimorphic yeast, has the abililty to switch its growth form between budding growth and hyphal growth. Since fungal growth involves secretory processes, spatial control of secretion should play a crucial role in such a morphogenetic transition. Brefeldin A (BFA), an inhibitor of the membrane trafficking system of eukaryotes, increases the occurrence of Golgi-like cisternae in the yeast. In the present study, BFA was used to obtain further insights into the spatial organization of secretory processes in hyphal growth ofC. albicans. BFA completely inhibited the formation and growth of germ tubes at a concentration of 35 μM or higher. Electron microscopy of BFA-untreated germinated cells revealed many vesicles in the apical region and Golgi-like cisternae in the cytoplasm. In cells treated with 35 μM BFA, the vesicles disappeared from the apical region, and, instead, stacked membrane cisternae and membrane-enclosed spherical dense bodies accumulated in the subapical region. These accumulated structures were positive for both polysaccharide staining and immunocytochemical staining with antibodies raised against cell surface antigens ofC. albicans, as were Golgi cisternae in BFA-untreated cells. In cells treated with a higher concentration of BFA (140 μM), the structures that appeared in cells treated with 35 μM BFA were no longer observed and the endoplasmic reticulum was extended and positive for polysaccharide staining. These results suggested that BFA affects different steps of membrane trafficking in a concentration-dependent manner. The accumulated structures induced by 35 μM BFA seemed to be the altered forms of Golgi cisternae. Their accumulation in the subapical region of the germ tube might indicate that the step(s) in membrane trafficking that are associated with the Golgi pathway are vectorially organized in hyphal growth ofC. albicans.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 57
    ISSN: 1615-6102
    Keywords: Antibodies ; Exine ; Immunocytochemistry ; Phenols ; Pollen ; Sporopollenin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Two different antibodies against bovine serum albumin (BSA)-p-coumaric acid-conjugates were produced and used to localize phenolic compounds in exines of pollen from different species,p-Coumaric acid (pC) was coupled to BSA either via the carboxy group (BSA-pC) or directly to the aromatic ring system (BSA-azopC). The polyclonal antibodies raised in rabbits were characterized by ELISA with homologous and heterologous antigens using turkey ovalbumin as carrier protein. The results showed that the two immune sera directed against BSA-pC and BSA-azo-pC, respectively, were specific forp-coumaric acid and structurally similar compounds. Only a very poor binding by acetic acid-ovalbumin-conjugates and no binding by turkey ovalbumin was detectable. The antibodies reacted with partially purified pollen walls and with highly purified exines. The intensity of the immune reaction was proved to be dependent upon the pollen source and the preparation of the pollen walls. Using light and electron microscopy, it was shown for the first time that, in the exines ofCucurbita maxima, antibody binding was predominantly observed in the region of the germ pore apertures, the outer foot layers, and in the micro- and macrospines. We conclude from this and other earlier published data that phenols are important structural compounds of sporopollenin.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 58
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 288 (1997), S. 471-483 
    ISSN: 1432-0878
    Keywords: Key words: Insulin receptor ; Insulin-like growth factor-1 receptor ; Immunocytochemistry ; Beta-endorphin ; Phosphotyrosine ; Pituitary ; Rat (Sprague Dawley)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. Previous investigations have demonstrated that peripheral insulin has a significant influence on brain function and that the interaction of insulin with neuropeptides in neuroendocrine regions may be pivotal for the regulation of body metabolism and energy balance. Since the various levels of interactions are only incompletely known, the focus of the present study has been the adenohypophysis of the rat, in which the presence and localization of insulin receptors and the structurally and functionally closely related insulin-like growth factor-1 (IGF-1) receptor has been investigated by light- and electron-microsopic immunocytochemistry. The two receptors are found on separate subpopulations of secretory cells of the pars distalis with a preponderance of IGF-1 receptors in a postero-lateral portion of large endocrine cells, insulin receptors being more widely dispersed throughout the pars distalis in a population of smaller, irregularly shaped cells. Insulin receptors, but not IGF-1 receptors, are also located in a subpopulation of secretory cells in the intermediate lobe. Phosphotyrosine, a marker for substrates of receptor tyrosine kinases, has been detected in numerous cells throughout the anterior and intermediate lobe, including the cell populations containing insulin or IGF-1 receptors, indicating their ability to transduce biological signals in the pituitary in vivo. Almost 90% of cells containing insulin receptors are also immunoreactive for beta-endorphin. In contrast, IGF-1 receptors are almost exclusively located on cells secreting follicle-stimulating hormone, suggesting a regulatory role of IGF-1 in the pituitary gonadotropin system. The relationship between β-endorphin and insulin receptors provides further evidence for the hypothesis that peripheral insulin acts as a regulatory hormone in the control of body energy homeostasis via various steps of the neuroendocrine axis, including opioid peptides in the hypothalamus and pituitary known to play an important role in the regulation of feeding behaviour.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 59
    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
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 60
    ISSN: 1432-0878
    Keywords: Key words: Placental stem villi ; Perivascular contractile sheath ; Molecules of adhesion plaques ; Extracellular matrix molecules ; Immunocytochemistry ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. In previous studies, we have shown that smooth muscle cells and myofibroblast subpopulations of the perivascular stem villous sheath of the human placenta contain focal adhesion plaques and talin immunoreactivity. The close association of these cells to elastic and collagen fibres have led to the assumption of a functional myofibroelastic unit within the perivascular stem villous sheath. Interactions between the extracellular matrix and smooth muscle cells depend on a variety of structural protein assemblies. In the present study, we examined, by immunocytochemistry, whether the molecular assembly of extracellular matrix proteins and molecules of focal adhesions, known to be essential for signal transduction in smooth muscle cells, are also found in smooth muscle cells of the perivascular stem villous sheath of the human placenta. Vascular and extravascular smooth muscle cells were immunoreactive for α-actinin, vinculin, paxillin and tensin, the integrin chains α1 and β1, and the basement membrane components laminin and heparan/-chondroitin sulfate proteoglycan perlecan. pp125FAK did not react. In the extracellular matrix of blood vessel walls and the perivascular stem villous sheath, we found immunoreactivity of fibronectin and collagen types I, VI and undulin (collagen type XIV). From our data we conclude that within the perivascular stem villous sheath, there exists a system of signal transduction molecules, indicating a cross talk between the smooth muscle cells of this sheath and their surrounding extracellular matrix.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 61
    ISSN: 1432-0878
    Keywords: Key words: Prohormone convertase ; PC1 ; PC2 ; Pituitary gland ; Corticotrope cell ; Melanotrope cell ; Immunocytochemistry ; Rana catesbeiana ; Buto japonicus ; Xeriopus laevis ; Rana brevipoda ; Buergeria japonica (Anura)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. Specific antisera against mammalian prohormone convertases PC1 and PC2 have been used to examine, light-immunocytochemically, the distribution of these enzymes in the pituitary gland of five different species of anuran amphibians (Rana catesbeiana, Bufo japonicus formosus, Xenopus laevis, Rana brevipoda porosa, and Buergeria japonica). A differential pattern of immunoreactivity of PC1 and PC2 was found among these species. Only PC1 was found in the corticotrope cells of the pars distalis in R. catesbeiana, B. japonicus formosus, and X. laevis. Only PC2 was observed in these cells in B. japonica, whereas both PC1 and PC2 were present in these cells in R. brevipoda porosa. PC2 immunoreactivity was always observed in melanotrope cells in the pars intermedia of all of the species, but it coexisted with PC1 immunoreactivity only in R. catesbeiana and X. laevis. The nerve fibers and terminals in the pars nervosa in all of the species were intensely immunopositive with both PC1 and PC2 antibodies. Immunoelectron microscopy on B. japonicus formosus and B. japonica, by means of double-labeling with gold particles of different sizes, revealed that almost all the adrenocorticotropin-positive secretory granules in the corticotrope cells and α-melanophore-stimulating-hormone-positive secretory granules in the melanotrope cells were also labeled with either PC1 or PC2 antibodies. This study suggests that PC1 and PC2 are involved in the intracellular proteolytic cleavage of proopiomelanocortin in amphibian pituitary glands, a situation similar to that proposed for mammals.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 62
    ISSN: 1432-0878
    Keywords: Key words: Leu-callatostatins ; Callatostatins ; Allatostatins ; Neuropeptides ; Peptide purification ; Immunocytochemistry ; Myoinhibition ; Codling moth ; Cydia pomonella (Tortricidae: Lepidoptera) (Insecta)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. A neuroendocrine peptide of the Leu-callatostatin family, LPVYNFGL-NH2, has been isolated from tissue extracts of 5th instar larvae of the codling moth, Cydia pomonella (Lepidoptera). It is identical to a peptide previously isolated from the blowfly, Calliphora vomitoria (Diptera). The distribution of this peptide within the tissues of C. pomonella has been mapped by immunocytochemistry using antisera raised against LPVYNFGL-NH2. Midgut endocrine cells contain Leu-callatostatin immunoreactivity, as do several paired Leu-callatostatin neurones in the brain and ventral nerve cord. Within the visceral nervous system, the frontal ganglion contains four Leu-callatostatin neurones. Axons from these cells combine with others originating from neurones in the brain and project within the nervi cardiostomatogastrici to innervate the tissues of the foregut. In particular, the oesophageal valve has a prominent ring of Leu-callatostatin-immunoreactive fibres. The synthetic peptide, LPVYNFGL-NH2, has a potent reversible inhibitory effect in vitro on all visible forms of spontaneous contractile activity of the foregut, including closure of the oesophageal valve. Complete myoinhibition is observed at peptide concentrations from 10−10 to 10−16 M. These results, in conjunction with the results of similar studies on cockroaches, crickets and flies, suggest that the Leu-callatostatins are a ubiquitous family of insect neuroendocrine peptides with an important role in the control of gut motility.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 63
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 288 (1997), S. 449-469 
    ISSN: 1432-0878
    Keywords: Key words: Neuronal ultrastructure ; Catecholamines ; Dopamine ; Immunocytochemistry ; Connections ; Quantitation ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. Interrelations of tyrosine-hydroxylase-immunoreactive afferent fibres with neuronal elements were studied in central, basal and intercalated nuclei of the rat amygdaloid complex. Comparison with dopamine-β-hydroxylase-immunoreacted and phenylethanolamine-N-methyltransferase-immunoreacted parallel sections indicated that the tyrosine-hydroxylase immunoreaction labelled preferentially dopaminergic axons. At the elec- tron-microscopic level, the majority of tyrosine-hydroxylase-immunoreactive axons possessed small boutons containing small clear vesicles and contacting dendrites, spines or somata of amygdala neurons, forming mostly symmetric synapses. They were often directly apposed to or in the vicinity of unlabelled terminals synapsing on the same structure. Synaptic density was highest in the central lateral part of the central nucleus. In the central and basal nuclei labelled axons synapsed preferentially on small dendrites and dendritic spines, and on somata of a few neurons. A detailed study of the neuronal ultrastructure showed that innervated somata possessed the differential characteristics displayed by the predominant neuron types in the medial and central lateral central nucleus and resembled the typical projection neurons in the basal nuclei. In the paracapsular intercalated cell groups the majority of neurons possessed intense perisomatic innervation by immunoreactive terminals. The results suggest that tyrosine-hydroxylase-immunoreactive, predominantly dopaminergic amygdaloid afferent fibres preferentially modulate the effect of extrinsic inputs into neurons of the central and basal nuclei, while a nonselective regulation is exerted upon the output of paracapsular intercalated neurons. It is suggested that this innervation pattern may be important for the coordinated integration of extrinsic and intraamygdaloid connections and thus for balanced output of the structure.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 64
    ISSN: 1432-0878
    Keywords: Key words: Hypothalamus ; GABA ; Neuropeptide Y ; Immunocytochemistry ; Development ; ontogenetic ; Oncorhynchus mykiss (Teleostei) ; Salmo trutta fario (Teleostei)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. The neuronal system of the saccus vasculosus of two species of trout was studied with immunocytochemical methods and carboindocyanine-dye (DiI) tract-tracing. The cerebrospinal-fluid-contacting neurons of the saccus were immunoreactive for gamma-aminobutyric acid (GABA), glutamic acid decarboxylase (GAD), and neuropeptide Y (NPY). Immunostaining of alternate sections of the saccus vasculosus of fry with anti-GAD and anti-NPY indicated that these substances were colocalized. The tractus sacci vasculosi and the neuropil of the nucleus sacci vasculosi were also immunoreactive to these substances. The GABA, GAD, and neuropeptide Y immunoreactivity of the saccus vasculosus system appeared early in trout ontogeny. After applying DiI to various levels of the tractus sacci vasculosi of adult trout, we observed massive bilateral saccular projections to the nucleus sacci vasculosi and could follow the course of the sacco-thalamic tract. This tract extended in the subependymal region of the thalamus rostral to the nucleus sacci vasculosi and split into two small tracts that reached the subhabenular-preoptic region. Sacco-thalamic fibers formed extensive periependymal plexuses along their trajectory. Interestingly, no clear evidence of the existence of a saccopetal system was obtained. On the basis of these results, we postulate that the saccus vasculosus system modulates the function of centers of the posterior tubercle and periventricular thalamus.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 65
    Electronic Resource
    Electronic Resource
    Springer
    Histochemistry and cell biology 106 (1996), S. 9-17 
    ISSN: 1432-119X
    Keywords: Key words Silver enhancement ; Immunogold-silver staining ; Immunocytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  The immunogold silver staining method (IGSS) is widely used as a sensitive and specific immunohistochemical visualisation technique. IGSS involves the specific deposition of metallic silver at the site of immunogold labelling and provides a means of visualisation at low magnification by light or electron microscopy. Silver developers for IGSS rapidly deposit metallic silver only at the site of heavy metals, including gold and silver, because of their catalytic activity. The developing solution contains the silver ions and reducing agent necessary for this reaction. Using different silver salts as ion donors and by selecting an appropriate temperature and pH, visible amounts of silver can be deposited in a few minutes at the site of colloidal gold labelling while little non-specific background deposition occurs. Inclusion of protective colloids in the solution can also be used to control the reaction. Although studies of the chemical basis of silver deposition around unlabelled colloidal gold date back to 1939, immunogold enhancement by silver was established in 1983. The IGSS method evolved from the combination of disparate photographic, histochemical and immunogold techniques which have been effectively combined and optimised over the last 10 years to provide a visualisation system which is well suited to many immunohistochemical studies.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 66
    Electronic Resource
    Electronic Resource
    Springer
    Histochemistry and cell biology 106 (1996), S. 9-17 
    ISSN: 1432-119X
    Keywords: Silver enhancement ; Immunogold-silver staining ; Immunocytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The immunogold silver staining method (IGSS) is widely used as a sensitive and specific immunohistochemical visualisation technique. IGSS involves the specific deposition of metallic silver at the site of immunogold labelling and provides a means of visualisation at low magnification by light or electron microscopy. Silver developers for IGSS rapidly deposit metallic silver only at the site of heavy metals, including gold and silver, because of their catalytic activity. The developing solution contains the silver ions and reducing agent necessary for this reaction. Using different silver salts as ion donors and by selecting an appropriate temperature and pH, visible amounts of silver can be deposited in a few minutes at the site of colloidal gold labelling while little non-specific background deposition occurs. Inclusion of protective colloids in the solution can also be used to control the reaction. Although studies of the chemical basis of silver deposition around unlabelled colloidal gold date back to 1939, immunogold enhancement by silver was established in 1983. The IGSS method evolved from the combination of disparate photographic, histochemical and immunogold techniques which have been effectively combined and optimised over the last 10 years to provide a visualisation system which is well suited to many immunohistochemical studies.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 67
    Electronic Resource
    Electronic Resource
    Springer
    Journal of plant growth regulation 15 (1996), S. 95-102 
    ISSN: 1435-8107
    Keywords: Cell cycle ; Cytokinin ; Soybean cells ; Glycine max ; Immunocytochemistry ; S phase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract An immunocytochemical method was used to determine the proportion of cells in the DNA synthesis (S phase) of the mitotic cycle in suspension cultures of soybean (Glycine max (L.) Merr. cv. Acme) callus of cotyledonary origin, the stably cytokinin-dependent tissue used in the cytokinin bioassay devised by Carlos O. Miller. A standard cell synchronization protocol involving hydroxyurea was used to demonstrate the applicability of the immunocytochemical method to this cell culture. Cells were brought to mitotic arrest by cytokinin withdrawal, and the cell division cycle was restarted by the addition of cytokinin. We have followed the pattern of resumption of S phase after the readdition of cytokinin. This pattern reveals the existence of three subpopulations of cells in cytokinin-starved cultures, consistent with the occurrence of three cytokinin-requiring events in the cell cycle: one in mitosis, one in S phase, and one in the G1 phase.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 68
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 284 (1996), S. 143-152 
    ISSN: 1432-0878
    Keywords: Key words: Leucokinins ; Immunocytochemistry ; Nervous system ; central ; Neuromodulators ; Cupiennius salei (Chelicerata)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. Leucokinin is a member of the myokinin peptide family. These myotropic peptides are widely distributed in arthropods. A specific antiserum immunoreactive to the neuroactive octapeptide leucokinin I (LKI) has been used to map neurones within the central nervous system of the central American wandering spider Cupiennius salei. The antiserum labels nine pairs of cell bodies and their axons. The somata are grouped near the joint of the optic lobes in the dorsal part of the supraoesophageal ganglion. The axons descend in a bundle, pass the oesophagus and divide to innervate the suboesophageal ganglion at three levels. In the dorsal-most layer, five small parallel fibres travel within the medio-central tract towards the opisthosomal neuromeres and give off small varicose projections into all leg neuromeres. In the middle layer, two neurones in the sensory-longitudinal tract 3 project into each leg neuromere. In the ventral layer, the two largest fibres (about 8 μm) run in the medio-ventral tract, each giving off a branch into all leg neuromeres. These first order arborizations have small second order arborizations in the ventral part of the leg neuromere and ascend to the five dorsal fibres in the medio-ventral tract where they form varicosities. The second order arborizations form extensive varicosities in the ventral part of the leg neuromere. These neurones may play a role in the intercellular communication between the sensory input and the motor output system, because they are represented in the dorsal sensory and the ventral motor neuropile. The ventral fibres resemble intersegmental interneurones and may function as modulators for leg motor neurones.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 69
    ISSN: 1432-0878
    Keywords: Key words: Vasotocin ; Sex dimorphism ; Bed nucleus of the stria terminalis ; Dehydration ; Immunocytochemistry ; In situ hybridization ; Domestic fowl
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. A strong sex dimorphism in the distribution of immunoreactive arginine-vasotocin (AVT) and AVT mRNA was observed in telencephalic and dorsal diencephalic areas of the domestic fowl using immunocytochemistry and in situ hybridization. Two subgroups of immunoreactive parvocellular perikarya surrounded by dense plexus of immunoreactive fibres were found within the bed nucleus of the stria terminalis and the dorsal part of the diencephalic paraventricular region of males. No signs of immunoreactivity were observed within corresponding regions of the female brain. Instead, in females a few scattered weakly stained perikarya were observed rostrally to the level of the anterior commissure, juxtapositioned to the nucleus accumbens and the floor of the lateral ventricle. The distribution of AVT mRNA containing cell profiles fully confirmed the immunocytochemical findings. Osmotic stress induced by water deprivation for 48 h had no influence on the number of immunoreactive or AVT mRNA containing parvocellular cell bodies. However, it resulted in an increase of immunoreactive cell area in the bed nucleus of the stria terminalis and dorsal diencephalon of 5.9 and 11.7%, respectively. We suggest that the sexually dimorphic vasotocinergic circuit may be involved in the co-ordination of behavioural and autonomic functions in response to environmental stress.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 70
    ISSN: 1432-0878
    Keywords: Key words: Auditory system ; Nervous system ; insect ; Interneurons ; Immunocytochemistry ; Inhibitory synapses ; Gryllus bimaculatus (Insecta)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. In the prothoracic ganglia of the cricket Gryllus bimaculatus two local auditory interneurones, ON1 and ON2, were labelled for electron microscopy by intracellular injection of horseradish peroxidase following physiological characterisation. The neurones branch in the median ventral association centre and the root of nerve 5 on both sides of the ganglion. As they are very similar in shape and position they may share a common embryological origin. Differences are found in the details of the fine branching pattern and in their physiology as ON1 is tuned particularly to low sound frequencies of 4–5 kHz whereas ON2 is more sensitive to frequencies above 8 kHz. Although the ON1 neurones inhibit each other and are involved in the inhibition of other auditory neurones they were not labelled by antibodies against the inhibitory transmitter GABA and their vesicles differ significantly from those in neurones that are. The same is true of the ON2 neurones whose vesicles also differ significantly from those in ON1 supporting light-microscope evidence that they may use different transmitters. The distribution of input and output synapses on the ipsilateral and contralateral branches of ON1 and ON2, and the proportion of the synapses made from and onto neuropilar processes immunoreactive for GABA was determined. In ON1 94% of the input synapses were received on the ipsilateral branches and 62% of the outputs made from the contralateral branches. This confirms previous physiological evidence that input is received ipsilaterally and output made contralaterally but the presence of some contralateral input and a significant ipsilateral output was unsuspected. Thirty percent of the input synapses on the ipsilateral side and 75% on the contralateral side were made from GABA-immunoreactive processes but processes postsynaptic to ON1 were rarely immunoreactive. The distribution of input synapses on ON2 was similar with 90% received on ipsilateral branches but a higher proportion of outputs (83%) was made from the contralateral side than in ON1. Thirty one percent of ipsilateral inputs were GABA-immunoreactive but only 14% on the contralateral side.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 71
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 283 (1996), S. 313-323 
    ISSN: 1432-0878
    Keywords: Key words: Neuropeptide Y ; Brain ; Pituitary ; Pineal organ ; Retina ; CSF-contacting neurons ; Immunocytochemistry ; Killifish ; Fundulus heteroclitus (Teleostei)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. The organization of the neuropeptide Y (NPY)-immunoreactive system in the forebrain, pineal organ and retina of a biweekly spawning fish (Fundulus heteroclitus) was investigated. Immunoreactivity was encountered in neurons of the nucleus olfactoretinalis, in the large population of neurons in the floor of the telencephalon, and in the nucleus entopeduncularis. Isolated somata were encountered in the hypophysiotropic hypothalamic nuclei, viz., the nucleus preopticus periventricularis, nucleus preopticus, and nucleus lateralis tuberis. Immunoreactive somata were also seen in the nucleus dorsomedialis thalami. The olfactory bulb was abundantly innervated by NPY fibers. The telencephalon showed thick radiating processes basally and terminal fields with modest to high densities in the dorsal and lateral regions. NPY-immunoreactive fibers were also conspicuous in the preoptic area, suprachiasmatic nucleus, tuberal hypothalamus, pituitary gland, and paraventricular thalamic regions; discrete CSF-contacting sites were also encountered. Of special interest was the occurrence of NPY immunoreactivity in fibers of the pineal stalk and organ. In the retina, some amacrine cells displayed immunoreactivity, while the inner plexiform layer revealed a well-developed pattern of NPY fibers different from that previously described for the goldfish.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 72
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 283 (1996), S. 461-468 
    ISSN: 1432-0878
    Keywords: Key words: Gills ; Na+ ; K+-ATPase ; Immunocytochemistry ; DASPMI ; Cell culture ; Oncorhynchus mykiss (Teleostei)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. The Na+,K+-ATPase (the sodium pump) plays a crucial role in ion transport in the fish gill. An immunocytochemical method has been optimized, using the mouse monoclonal antibody IgG α5, raised against the αsubunit of the avian sodium pump, to localize Na+,K+-ATPase in fish gill cells. The method appears to be successful for the immunolocalization of Na+,K+-ATPase in both paraffin-embedded gill tissue sections and primary cultures of fish gill epithelial cells. The immunostaining has demonstrated that Na+,K+-ATPase-positive cells are mainly localized on the primary lamellae, in the interlamellar region, which is in agreement with the distribution of ion-transporting cells, also called chloride cells, as shown by electron microscopy. Na+,K+-ATPase-positive cells have been demonstrated for the first time in primary cultures of gill epithelial cells. Comparative labeling studies of primary cultures have shown that sites of Na+,K+-ATPase-positive cells correspond to sites of cells labeled with dimethylaminostyrylmethyl-pyridiniumiodine, a fluorescent mitochondrial probe for ion-transporting cells. The immunocytochemical detection method for Na+,K+-ATPase in cells is proposed as an easy and specific Na+-transport-related method to characterize and localize ion-transporting cells in primary cultures and in tissue sections of fish gill epithelium.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 73
    ISSN: 1432-0878
    Keywords: Key words: AKH/RPCH peptide family ; Insect brain ; Corpora cardiaca ; Immunocytochemistry ; Enzyme immunoassay ; Periplaneta americana ; Leucophaea maderae (Insecta) ; Tegenaria atrica (Chelicerata)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. An antiserum against the octapeptide Pea-CAH-I, a member of the adipokinetic hormone/red pigment-concentrating hormone family, has been produced for immunocytochemical staining in insects and various other invertebrate species. The anti-Pea-CAH-I serum stains the glandular corpora cardiaca cells of those insect species that synthesize identical or structurally similar peptides. In the corpora cardiaca of species producing peptides with a different C-terminus, these cells remain unstained. Pea-CAH-I-like immunoreactivity has also been found in neurons of the central nervous system of all invertebrate orders studied. The antiserum recognizes the C-terminal sequence Pro-Asn-Trp-NH2 of the Pea-CAH-I molecule as established by enzyme immunoassay. The widespread Pea-CAH-I-like immunoreactivity in all nervous systems of the studied animals probably does not reflect the presence of Pea-CAH-I but the occurrence of peptides carrying similar epitopes.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 74
    ISSN: 1432-0878
    Keywords: Key words: Phagocytosis ; Insect hemocytes ; Lectins ; Fungal entomopathogens ; Ultrastructure ; Immunocytochemistry ; Cytoskeleton ; Spodoptera exigua (Insecta) ; Paecilomyces farinosus (Fungi-Deuteromycotina)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. Phagocytosis of blastospores of the fungal entomopathogen Paecilomyces farinosus by granular hemocytes from larvae of Spodoptera exigua (beet armyworm) was studied. Blastospores were opsonized with a galactose-specific lectin purified from S. exigua hemolymph or with peanut agglutinin prior to incubation with hemocytes. Observations of thin sections revealed that pseudopodia extending from granulocytes attached to ligands (lectins, lectin conjugates) on the blastospores, and that the ligands became detached from the fungal surfaces and were endocytosed by granulocytes via coated pits on the plasma membrane. Coated vesicles bearing the endocytosed molecules appeared to be transported to the hemocytic granules. In other cases, ligand still coated the blastospores after phagocytosis and may have later concentrated within the phagosome along with digested fungal cell wall components. Phagocytosis of blastospores and clustering of a biotinylated lectin conjugate on or within the granulocytes were inhibited by drugs targeting cytoskeletal elements. Actin was concentrated in the pseudopodia of phagocytic granulocytes and may be directly associated with lectin receptor(s). Microtubules were abundant in the granulocytes, sometimes in specific regions.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 75
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 285 (1996), S. 165-169 
    ISSN: 1432-0878
    Keywords: Key words: Ciliary axoneme ; Cones ; Cytoskeleton ; Immunocytochemistry ; Microtubules ; Outer segments ; Photoreceptor cells ; Xenopus laevis (Anura)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. The ciliary axoneme in photoreceptors from the retina of Xenopus laevis was examined by immunofluorescent staining of tubulin throughout the light/dark cycle. The immunofluorescent axoneme extended along only part of the length of rod outer segments but the entire length of cone outer segments. Both the cone axoneme and outer segment elongated during the day and shortened (presumably by shedding) during the night. Fragments of immunofluorescent axonemes were found within packets of outer segment material breaking off from cone tips. These findings show that the ciliary axoneme in the Xenopus retina is replaced during the renewal of outer segments in cones. No evidence has been found for renewal of the axoneme in rods, and thus the stability of the ciliary axoneme may differ in rod and cone photoreceptors.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 76
    ISSN: 1432-0878
    Keywords: Key words: Dopamine ; Invertebrate CNS ; Immunocytochemistry ; Biogenic amine ; Callinectes sapidus (Crustacea)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. Injection of dopamine initiates a posture in the blue crab, Callinectes sapidus, identical to courtship display behavior of the male crab. The threshold for proctolin-induced rhythmic components of courtship display is lowered in preparations when dopamine is co-applied with proctolin. To elucidate the anatomical substrate of this behavior, immunocytochemistry was used to map dopamine-immunoreactive neurons. Courtship display is sex-specific, and dependent on the hormonal, developmental, and seasonal state of the animal. We compared the distribution of dopamine-like immunoreactivity between adults and juveniles of both sexes across seasons, with hormonal alteration, and with the distribution of proctolin-like immunoreactivity. Dopamine-like immunoreactivity was found throughout the nervous system in identical patterns between the sexes and hormonal states. Differences were found between juveniles and adults that are not obviously correlated with the development of behavior. Two areas of staining were of interest: neurites that longitudinally traverse and terminate in the posterior ventral nerve cord, and a neuron in the esophageal ganglion that has projections to the pericardial organ. The results do not suggest that proctolin-like and dopamine-like immunoreactivity co-localize, but in the subesophageal ganglion there was a region of close proximity.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 77
    ISSN: 1432-0878
    Keywords: Key words: GABA (gamma-aminobutyric acid) ; Nervous system ; central ; Nervous system ; peripheral ; Immunocytochemistry ; Lumbricus terrestris (Annelida)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. The distribution of neurons immunoreactive for γ-aminobutyric acid was studied in the nervous system of Lumbricus terrestris (Oligochaeta). In the cerebral ganglion, the 86 cells immunoreactive for γ-aminobutyric acid represented 4.0% of the nerve cells in the brain, had a diameter of 12–50 μm, and were arranged in seven groups. Small-sized (18–30 μm) immunoreactive neurons occurred in the circumpharyngeal connectives. The axons of most immunoreactive neurons of the cerebral ganglion richly arborized in the ventral part of the neuropil and some could also be traced in the circumpharyngeal connectives. The subesophageal ganglion contained 94 immunoreactive cells (6.7% of the cells of this ganglion), also divided into seven groups, and with a diameter of 8–55 μm. The axons of the labeled neurons ran to the central neuropil giving both contra- and ipsilateral processes. Altogether 108 neurons in each ganglion (8.0% of their cells) of the ventral cord were immunopositive. Four labeled cell groups were present in the rostral and caudal part of each ganglion. Axons of these immunoreactive cells arborized in the central neuropil and projected to the segmental nerves. The stomatogastric ganglia and the enteric plexus also contained immunoreactive neurons. Many small elongated immunoreactive cells occurred in the gut epithelium. Postembedding immunogold electron microscopy revealed that immunoreactive varicosities mainly contained small pleomorphic (24 nm) agranular synaptic vesicles and some small granular (50 nm) vesicles.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 78
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 286 (1996), S. 69-80 
    ISSN: 1432-0878
    Keywords: Key words: Growth hormone ; Growth hormone receptors ; Growth hormone-binding proteins ; Immune system ; Immunocytochemistry ; Domestic fowl (Aves ; Phasianiformes)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. It is well established that the activity and proliferation of lymphoid cells and lymphoid organs are stimulated by growth hormone. These actions on lymphoid cells may be direct or mediated by actions on the epithelial and non-immune tissue cells that regulate immune function. The occurrence and cellular localization of growth hormone receptors in immune tissues has therefore been investigated to determine the target-sites of growth hormone action. Growth hormone receptor mRNA was first detected by Northern blotting in the spleen, bursa of Fabricius, and thymus of domestic fowl. In addition to the 4.4-kb transcript thought to encode the full-length growth hormone receptor, smaller transcripts of 2.8 kb and 1.0 kb, which may encode growth hormone-binding proteins, were also occasionally observed. Further analysis using the polymerase chain reaction revealed that mRNA sequences encoding the extracellular and intracellular domains of the growth hormone receptor were present in all tissues and highly homologous with hepatic transcripts. Translation of these transcripts also occurs in immune tissues, since immunoreactive growth hormone-binding proteins or growth hormone receptors of approximately 56 kDa were detected in hepatic, splenic, thymic, and bursal extracts. Immunocytochemistry of these tissues subsequently revealed that macrophages probably contain the bulk of this immunoreactivity, although some thymic medullary epithelial cells (including Hassall’s corpuscles) and splenic ellipsoids and interdigitating cells were also immunoreactive. This immunoreactivity is present in immune tissues of newly hatched and adult chickens. Importantly, B-lymphocytes were rarely, if ever, immunoreactive, and T-lymphocytes containing growth hormone receptors or binding proteins were not observed. These results suggest that a number of primary (thymus and bursa) and secondary (spleen) lymphoid tissues in the chicken contain growth hormone receptors and are thus target-sites for growth hormone action. The distribution of growth hormone receptor/growth hormone-binding protein immunoreactivity in these tissues would further suggest that growth hormone plays a major role in macrophage proliferation and/or activity and may indirectly affect lymphocyte maturation and storage via effects on thymic and splenic stromal cells.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 79
    ISSN: 1432-0878
    Keywords: Key words: Transplantation ; Fetal ventral mesencephalic grafts ; 6-Hydroxydopamine ; Glial-cell-line-derived neurotrophic factor ; Tyrosine hydroxylase ; Immunocytochemistry ; Rat (Sprague Dawley)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. Previous reports have indicated that grafting of fetal ventral mesencephalic tissue to the nigra region of animals unilaterally lesioned with 6-hydroxydopamine (6-OHDA), in conjunction with kainate injection between the nigra and striatum, restores nigrostriatal tyrosine hydroxylase immunoreactivity. Glial-cell-line-derived neurotrophic factor (GDNF), a potent trophic factor for dopaminergic neurons, has been found to be upregulated by kainate. We have investigated the bridging effect of GDNF injection on intra-nigral transplants. Adult Sprague-Dawley rats were anesthetized and unilaterally injected with 6-OHDA into the medial forebrain bundle. The completeness of lesions was tested by measuring methamphetamine-induced rotations. Some 1–2 months after 6-OHDA administration, fetal ventral mesencephalic tissues were grafted into the lesioned nigral area followed by injection of 100 μg GDNF, along a tract from the nigra to striatum. Animals receiving transplantation and GDNF injection showed a significant decrease in rotation 1–3 months after grafting. Immunocytochemical studies indicated that tyrosine-hydroxylase-positive neurons and fibers were present in the nigra and striatum, respectively, after grafting. No effects of similarly injected brain-derived neurotrophic factor were seen. These results indicate that fetal nigral transplantation and GDNF injection restore the nigrostriatal dopaminergic pathway in Parkinsonian animals and support the hypothesis of trophic activity of GDNF on midbrain dopaminergic neurons.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 80
    ISSN: 1432-0878
    Keywords: Key words: Chromaffin cells ; Neurotrophic factor ; RT-PCR ; Immunocytochemistry ; Western blotting ; Rat (Hannover-Wistar) ; Bovine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. Glial cell line-derived neurotrophic factor (GDNF) is a widely distributed member of the transforming growth factor-β superfamily and a potent neurotrophic molecule for several neuron populations in the peripheral and central nervous system. We show here that adrenal medullary chromaffin cells synthesize GDNF mRNA and contain immunoreactive GDNF protein. GDNF immunoreactivity can be found as early as embryonic day 16 in chromaffin progenitor cells of the rat adrenal gland and becomes more prominent with age. Most of the chromaffin cells within the adult rat adrenal medulla are GDNF immunoreactive, including both the noradrenergic and adrenergic subpopulations. The functions of adrenal medullary GDNF are still enigmatic but may include both auto/paracrine roles and retrograde trophic support of preganglionic neurons in the spinal cord or of sensory neurons that innervate chromaffin cells.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 81
    ISSN: 1432-0878
    Keywords: Key words: Calsensin ; Calcium-binding protein ; Immunocytochemistry ; Neurons ; Leeches ; Hirudo medicinalis ; Haemopis marmorata ; Macrobdella decora (Annelida)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. By immunocytochemistry the distribution and developmental expression of the small EF-hand calcium-binding protein calsensin in the peripheral (PNS) and central nervous system (CNS) of the three hirudinid leech species Haemopis, Hirudo, and Macrobdella was compared. Labeling with calsensin-specific antibodies demonstrated that there was a pronounced difference in the distribution of calsensin immunoreactivity in the CNS of these leeches. In Haemopis more than 70 neurons were labeled, whereas the number in Hirudo was 51 and in Macrobdella only 8. Furthermore, the expression of calsensin in identified cells common to all three leech species also differed. Immunoblot analysis indicated that this variability was not likely to be due to multiple proteins or isoforms being recognized by the calsensin antibody. Labeling of embryos in various stages of development shows that the ontogeny of calsensin expression in the CNS is a gradual process with some neurons expressing calsensin immediately after completion of neurogenesis, about one-third of the way through embryogenesis, and others expressing calsensin only postembryonically. In contrast to the variability in the pattern and temporal expression by CNS neurons, the early embryonic calsensin expression in a small subgroup of sensillar PNS neurons was a shared feature by all three leech species. These findings suggest that calsensin may have different functional properties in CNS and PNS neurons.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 82
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 283 (1996), S. 169-172 
    ISSN: 1432-0878
    Keywords: Key words: Adrenomedullin ; Nitric oxide ; Nervous system ; Gut ; Immunocytochemistry ; Marthasterias glacialis (Echinodermata)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. The nervous system of the starfish Marthasterias glacialis was investigated immunocytochemically using an antiserum specific for adrenomedullin (AM), a new regulatory peptide. Immunoreactivity was only found in nerves of the basiepithelial plexus of cardiac and pyloric stomachs and pyloric caeca, while the radial nerve cords and the other digestive organs were negative. The strongest AM-like immunoreactivity was located in the current-producing areas of the cardiac stomach. The distribution of this peptide suggests different functions in echinoderms involving regulation of muscle movement and neurotransmission. The presence of an AM-like substance in echinoderms points to an early phylogenetic origin for this regulatory system.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 83
    ISSN: 1432-0878
    Keywords: Key words: Pars tuberalis ; Gonadotrophs ; Ovariectomy ; Seasonal changes ; Immunocytochemistry ; Sheep
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. This study investigated whether season or long-term ovariectomy influence the presence, distribution and density of immunoreactive cells in the ovine pars tuberalis. Three groups of ewes were used: breeding season (BS; n=5), anoestrous (AS; n=8) and ovariectomised (OVX; n=4). Two rams were also investigated for possible sex-dependent differences. Employing standard immunocytochemical techniques, paraformaldehyde-fixed sagittal pars tuberalis and pars distalis sections were immunoreacted against luteinising hormone, luteinising hormone β-subunit, thyroid-stimulating hormone, prolactin, growth hormone, β-endorphin and adrenocorticotrophic hormone. Numerous gonadotrophs were detected in the anteroventral region of the pars tuberalis and there was no significant difference in the density (gonadotrophs/0.01 mm2; BS: 44±13, AS: 29±2, OVX: 27±4) or percentage of total cells (%; BS: 48±8, AS: 45±4, OVX: 49±2); the rams also appeared similar (27±2 gonadotrophs/0.01 mm2; 49±1%). In contrast, few gonadotrophs (less than 1%) were detected in the anterodorsal and posterior pars tuberalis regions. Apart from occasional thyrotrophs in the anteroventral pars tuberalis (less than 4%), no other pars distalis hormone-containing cells were detected in the pars tuberalis. This study demonstrates, therefore, that the anteroventral pars tuberalis represents an enriched population of immunoreactive gonadotrophs, whose number and distribution is similar in variable endocrine states. The protein phenotype(s) of cells in the other pars tuberalis regions remains undetermined.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 84
    ISSN: 1432-0878
    Keywords: Key words: Salmon gonadotropin-releasing hormone ; Immunocytochemistry ; In situ hybridization ; Olfactory system ; Telencephalon ; Terminal nerve ; Salmon homing migration ; Oncorhynchus keta (Teleostei)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. Cytophysiology of gonadotropin-releasing-hormone neurons in chum salmon (Oncorhynchus keta) was examined before and after upstream migration by an immunocytochemical technique with a specific antiserum to salmon gonadotropin-releasing hormone and an in situ hybridization technique with an oligonucleotide encoding salmon gonadotropin-releasing-hormone precursor (pro-salmon gonadotropin-releasing hormone). In the forebrain (olfactory nerve, olfactory bulb, telencephalon, and preoptic area), salmon gonadotropin-releasing hormone-immunoreactive neurons and neurons showing signals for pro-salmon gonadotropin-releasing-hormone mRNA were compared between fish from the coastal sea and those from the spawning ground. Neurons in the dorsal region of the olfactory nerve and in the ventral region of the transitional area between olfactory nerve and olfactory bulb showed strong salmon gonadotropin-releasing-hormone immunoreactivity and strong hybridization signals in fish from the coastal sea, but these activities and signals were not observed or were decreased in number in fish from the spawning ground. The neurons in the olfactory bulb, telencephalon, and preoptic area consistently revealed salmon gonadotropin-releasing-hormone immunoreactivity and hybridization signals, and the hybridization signals of salmon gonadotropin-releasing hormone in the telencephalon and the preoptic area were stronger in fish from the spawning ground than in those from the coastal sea. These findings suggest that salmon gonadotropin-releasing-hormone neurons in the olfactory nerve and the transitional area between olfactory nerve and olfactory bulb have different patterns of hormone production than those in the telencephalon and the preoptic area.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 85
    ISSN: 1432-0878
    Keywords: Key words: Histamine ; Amines ; biogenic ; Immunocytochemistry ; Nervous systems ; insect ; Gryllus bimaculatus (Insecta)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. The present study demonstrates the immunocytochemical localisation of the biogenic amine, histamine (HA), in interneurons within the ventral nerve cord of the cricket, Gryllus bimaculatus. Analysis of whole-mount preparations combined with histology of serial sections reveals a constant number of HA-immunoreactive (HA-ir) neurons in the suboesophageal (n=8), thoracic (n=4) and abdominal ganglia (females/males n=24/20). Except for the suboesophageal and prothoracic ganglion, each thoracic and abdominal neuromere contains one pair of bilateral-symmetric HA-ir somata in a medio-ventral position. Axons from HA-ir cells in the thorax extend anteriorly and share common projection areas in thoracic associative neuropils; they terminate in the brain. HA-ir cells also display efferent descending axons. Extending posteriorly, these axons give rise to varicose HA-ir fibre plexuses on the surface of nerve 1 of the abdominal ganglia. In the suboesophageal ganglion, processes from a bilateral symmetric group of clustered HA-ir cells ascend into the tritocerebrum of the brain and further project into the frontal ganglion and the recurrent nerve. Ultrastructural analysis reveals dense-core vesicles, indicative of non-synaptic secretion, in HA-ir elements within the stomatogastric nervous system. Arborisations of HA-ir neurons are present in all major neuropil regions of the ventral nerve cord and display characteristic varicose structures also detected in other types of amine-containing cells. Central HA-ir varicose projections in dorsal and ventral neuropils are located in close apposition to the ganglionic surface. The wide-spread innervation of all neuromeres by HA-ir interneurons and the identification of possible neurohemal release sites suggest a general role of HA as a neuroactive substance, including neuromodulatory and neurohormonal functions.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 86
    ISSN: 1432-0878
    Keywords: Key words: NO/cGMP pathway ; Testis ; Leydig cells ; Immunocytochemistry ; RIA ; Cell culture ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. In this study we sought to determine whether the main components of the nitric oxide (NO) pathway are localized within the Leydig cells of the human testis and whether the soluble guanylyl cyclase (sGC), the enzyme that accounts for NO effects, is functionally active in these cells. Using an amplified immunocytochemical technique, immunoreactivity for nitric oxide synthase (NOS-I), sGC and cyclic guanosine monophosphate (cGMP) was detected within the cytoplasm of human Leydig cells. Distinct differences in staining intensity were found between individual Leydig cells, between cell groups and between Leydig cells of different patients. By means of a specific cGMP-RIA, a concentration-dependent increase in the quantity of cGMP was measured in primary cultures of human Leydig cells following exposure to the NO donor sodium nitroprusside. In addition, NOS-I immunoreactivity was seen in Sertoli cells, whereas cGMP and sGC immunoreactivity was found in Sertoli cells, some apically situated spermatids and residual bodies of seminiferous tubules. Dual-labelling studies and the staining of consecutive sections showed that there are several populations of Leydig cells in the human testis. Most cells were immunoreactive for NOS-I, sGC and cGMP, but smaller numbers of cells were unlabelled by any of the antibodies used, or labelled for NOS-I or cGMP alone, for sGC and cGMP, or for NOS-I and sGC. These results show that the Leydig cells possess both the enzyme by which NO is produced and the active enzyme which mediates the NO effects. There are different Leydig cell populations that probably reflect variations in their functional (steroidogenic) activity.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 87
    ISSN: 1432-0878
    Keywords: Key words: Met-enkephalin ; Opioids ; Immunocytochemistry ; Lymnaea stagnalis (Mollusca)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. The distribution of an opioid peptide related to YGGFMRF was determined in the CNS and other organs of the pond snail, Lymnaea stagnalis, by RIA and immunocytochemistry. RIA revealed the highest levels in the CNS (1 pmol/organ) and penis (400 fmol/organ). There were also significant levels in the haemolymph, most of which was not associated with haemocytes (580 fmol/ml). Both serial section and whole-mount immunocytochemistry of the CNS revealed immunoreactive cells in every ganglion with the majority in the cerebral and pedal ganglia. In the pedal ganglia some of the immunoreactive cells were close to the cells of the A-cluster, which are known to respond to opioids, and could innervate them. In the cerebral ganglia the immunoreactive cells included a group of neurosecretory cells, the caudo dorsal cells (CDCs) and the terminals of these cells in the cerebral commissure were also stained. The CDCs secrete peptides into the haemolymph and so could be the source of the YGGFMRF immunoreactivity. Immunoreactivity (including the CDCs) was observed in locations that correspond to those reported for other fragments of proenkephalin, such as Met- and Leu-enkephalin, suggesting that they may share a common precursor, a Lymnaea proenkephalin. A map of the 358 YGGFMRF-immunoreactive cells in the CNS is presented, many of which have not been previously identified.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 88
    ISSN: 1432-0878
    Keywords: Key words: IgE receptor ; Gamma subunit ; RBL-2H3 cells ; Immunocytochemistry ; Electron microscopy Rat (Sprague Dawley) ; Mouse (Balb/c)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. The high affinity IgE receptor on mast cells and basophils is composed of 3 subunits, alpha, beta and gamma. A polyclonal antibody was raised in rabbits to a 13 amino acid synthetic peptide corresponding to the amino terminal portion of the gamma subunit. The antiserum was screened using Western blots of solubilized RBL-2H3 cells and 125I goat anti-rabbit IgG. After purification of the serum on a protein G column, RBL-2H3 cells, mouse mast cells, and human basophils showed a doublet at 20 000 kDa. When 125I labeled, saponin-permeabilized cells were immunoprecipitated with the anti-gamma antibody, all 3 subunits of the IgE receptor complex coprecipitated. Furthermore, binding of the antibody to the cell surface did not induce histamine release. By immunofluorescence of fixed cells, the receptor was evenly distributed in the RBL-2H3 cells. Although no capping was observed when the cells were incubated with the antibody prior to fixation, the antibody did stimulate endocytosis when it was bound to the cells at 25° C or at 37° C, but not at 4° C. Binding of the antibody to the RBL-2H3 cells also induced cell spreading and ruffling of the plasma membrane. The results of this study indicate that the gamma subunit of the high affinity IgE receptor may play a role in signal transduction.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 89
    ISSN: 1432-0878
    Keywords: Key words: GABA receptor ; RDL subunit ; Nervous system ; Immunocytochemistry ; Drosophila melanogaster (Insecta)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. An antibody raised against a peptide based on the C-terminal derived amino acid sequence from a cloned Drosophila melanogaster (fruit fly) gene, Rdl (resistant to dieldrin), was used to investigate localization of a GABA receptor subunit in adult male D. melanogaster. Many regions in the brain and thoracic ganglia were stained with this antibody. For example, staining was detected in the medulla, lobula and lobular plate optic neurpiles. Also stained were the antennal lobe glomeruli, the ellipsoid body of the central complex and the mushroom bodies. These results suggest possible roles for an RDL-like GABA receptor subunit in the processing of olfactory, visual and mechanosensory information in the nervous system of D. melanogaster.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 90
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 284 (1996), S. 489-493 
    ISSN: 1432-0878
    Keywords: Key words: Ovarian follicles ; Immunocytochemistry ; Cytokeratins ; Vimentin ; Actin ; Tubulin ; Podarcis sicula (Lacertilia)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. We report the immunolocalization of intermediate filament proteins (vimentin and cytokeratins) in the previtellogenic ovarian follicle of the lizard Podarcis sicula. Vimentin is present, in accordance with their mesenchymal origin, in all the cells of the polymorphic follicular epithelium (small, intermediate and pyriform). Cytokeratin, absent from the small follicle cells, is present in those cells (intermediate and pyriform) connected to the oocyte by an intercellular bridge. In particular, this protein surrounds the nucleus in the pyriform cells and is mainly localized at the apex adjacent to the oocyte surface; it forms a network, that crosses the zona pellucida through the intercellular bridge and appears to be continuous with a cortical ring of cytokeratin in the oocyte. The presence of a cytokeratin cytoskeleton in the pyriform cells in continuity with that of the oocyte lends support to the previously reported hypothesis that, during oogenesis in Podarcis sicula, somatic cells constitute an integral system with the germ cell and provide for its growth. Preliminary observations indicating the presence of actin and tubulin inside the cytoplasmic bridges connecting the pyriform cells to the oocyte are in agreement with an involvement of these connections in the transfer of cytoplasmic materials.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 91
    Electronic Resource
    Electronic Resource
    Springer
    Protoplasma 195 (1996), S. 68-77 
    ISSN: 1615-6102
    Keywords: Endosperm ; Immunocytochemistry ; Opaque-2 ; Protein bodies ; Tubular arrays ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The seed storage proteins of maize (Zea mays L.) are synthesized during endosperm development on membrane-bound polyribosomes. Protein body formation in normal genotypes occurs via a sequential deposition of the various types of zeins, and leads to the formation of spherical structures with a diameter of about l μm. In the endosperm mutantopaque-2 the level of one zein class is reduced; these kernels exhibit an opaque phenotype instead of the vitreous phenotype displayed in normal genotypes, presumably due to the decrease in total zein protein at the time of desiccation. Previous microscopic examination ofopaque-2 protein bodies at 22 DAP (days after pollination) showed that the protein bodies were morphologically similar to those of normal genotypes. However, the endosperm ofopaque-2 maize at 14 DAP contains tubular arrays within the rough endoplasmic reticulum. These tubular arrays are tightly associated with the developing protein bodies. Long strands of tubules, sometimes 10 μm in length, are observed in the endosperm, and partially formed protein bodies often seem to be forming directly from these tubular arrays. No immunostaining is associated with this tubular material when any of the anti-zein antibodies are used.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 92
    Electronic Resource
    Electronic Resource
    Springer
    Molecular genetics and genomics 250 (1996), S. 750-760 
    ISSN: 1617-4623
    Keywords: Key words lys3a ; CpG island ; Transient expression ; Particle bombardment ; Immunocytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract  B- and C-hordein gene transcription is severely reduced in the endosperm of the regulatory barley mutant lys3a, and this is correlated with persistent hypermethylation of the promoters. In contrast, D-hordein is expressed at normal levels in the mutant. To confirm the connection between methylation and transcriptional activity, a genomic D-hordein clone was isolated and sequenced. The nucleotide composition of the promoter region revealed a CpG island and methylation analysis, using bisulphite treatment of genomic DNA, confirmed that the D-hordein promoter is unmethylated in endosperm and leaf tissue. Immunocytochemical studies localized D-hordein to the reticular component of protein bodies in both the wild-type Bomi and lys3a. Transient expression of GUS reporter gene constructs in barley endosperm, following transfection by particle bombardment revealed the D-hordein promoter to be 3–5 fold more active than B- or C-hordein promoters. Comparison of transient expression in Bomi and lys3a endosperm demonstrated that the activities of the unmethylated D-hordein and the Hor1-14 C-hordein promoters were equivalent, while the activities in the mutant of the Hor1-17 C-hordein and the Hor2-4 B-hordein promoters were reduced two- and tenfold, respectively. Methylation of plasmids in vitro prior to expression severely inhibited B- and D-hordein promoter activities. Based on these observations two categories of promoters for endosperm-specific expression of storage proteins are recognized and a model involving methylation and modulation of chromatin structure in the regulation by the Lys3 gene is presented.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 93
    ISSN: 1617-4623
    Keywords: lys3a ; CpG island ; Transient expression ; Particle bombardment ; Immunocytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract B- and C-hordein gene transcription is severely reduced in the endosperm of the regulatory barley mutantlys3a, and this is correlated with persistent hypermethylation of the promoters. In contrast, D-hordein is expressed at normal levels in the mutant. To confirm the connection between methylation and transcriptional activity, a genomic D-hordein clone was isolated and sequenced. The nucleotide composition of the promoter region revealed a CpG island and methylation analysis, using bisulphite treatment of genomic DNA, confirmed that the D-hordein promoter is unmethylated in endosperm and leaf tissue. Immunocytochemical studies localized D-hordein to the reticular component of protein bodies in both the wild-type Bomi andlys3a. Transient expression ofGUS reporter gene constructs in barley endosperm, following transfection by particle bombardment revealed the D-hordein promoter to be 3–5 fold more active than B-or C-hordein promoters. Comparison of transient expression in Bomi andlys3a endosperm demonstrated that the activities of the unmethylated D-hordein and theHor1-14 C-hordein promoters were equivalent, while the activities in the mutant of theHor1-17 C-hordein and theHor2-4 B-hordein promoters were reduced two- and tenfold, respectively. Methylation of plasmids in vitro prior to expression severely inhibited B- and D-hordein promoter activities. Based on these observations two categories of promoters for endosperm-specific expression of storage proteins are recognized and a model involving methylation and modulation of chromatin structure in the regulation by theLys3 gene is presented.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 94
    ISSN: 1432-0878
    Keywords: Key words: Nucleus of the solitary tract ; Ventrolateral medulla ; Retrograde tracing ; Immunocytochemistry ; Rat (Sprague Dawley)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. Combinations of retrograde tracing with detection of Fos (the protein product of the immediate early gene c-fos) following electrical stimulation of the central nucleus of the amygdala were used to explore: (1) the connectivity of activated (Fos-positive) neurons in the ventrolateral medulla with the nucleus of the solitary tract; (2) the connectivity of activated neurons in the nucleus of the solitary tract with the ventrolateral medulla; (3) the proportion of activated catecholaminergic neurons that project to the nucleus of the solitary tract or to the ventrolateral medulla. Retrograde tracer was injected into the nucleus of the solitary tract or the ventrolateral medulla. After 5 days, stimulation for 60 min induced a statistically significant increase in the number of Fos-immunoreactive neurons in the ventrolateral medulla that project to the nucleus of the solitary tract and in the number of Fos-positive neurons in the nucleus of the solitary tract that project to the ventrolateral medulla. Of the neurons activated by stimulation of the central nucleus of the amygdala, 20% in the ventrolateral medulla and 3% in the nucleus of the solitary tract contained the retrograde tracer and were also immunopositive for tyrosine hydroxylase, the enzyme responsible for synthesis of catecholamines.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 95
    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
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 96
    ISSN: 1432-0878
    Keywords: Key words: Diuretic hormone ; Endocrine cells ; Midgut ; Malpighian tubules ; Bioassay ; Immunocytochemistry ; Locusta migratoria (Insecta)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. This is an investigation of an endocrine cell type in the midgut of the migratory locust Locusta migratoria. This cell type is found in the posterior region of the midgut and is especially common in the ampullae through which Malpighian tubules drain into the gut at the midgut-hindgut junction. Strong Locusta diuretic hormone-like immunoreactivity in these cells was colocalized with FMRFamide- and substance P-like immunoreactivities. At the ultrastructural level, immunoreactivity for Locusta diuretic hormone was found in spherical granules (mean diameter of 450 nm), the contents of which showed variable electron density. Fractionation of a methanolic extract of the ampullae by reversed-phase high performance liquid chromatography revealed the presence of two peaks of Locusta diuretic hormone-like immunoreactive material, both of which stimulate cyclic AMP production by isolated Malpighian tubules. The more hydrophobic material is most likely Locusta diuretic hormone, which has the same retention time when chromatographed under identical conditions.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 97
    ISSN: 1432-0878
    Keywords: Key words: Subcommissural organ ; Secretory glycoproteins ; Antibodies ; Immunochemistry ; Immunocytochemistry ; Lectins ; Chick embryo (White Leghorn)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. The subcommissural organ is an ependymal brain gland that secretes, into the ventricular cerebrospinal fluid, high molecular weight glycoproteins that form Reissner’s fiber. Precursor and processed forms of secretion have been demonstrated by immunoblotting in the subcommissural organ of mammals and fish. In the chicken only a processed form has as yet been identified. In the present report, we have studied the subcommissural organ of 13-day-old chick embryos using (1) an antiserum against bovine Reissner’s fiber, and (2) the lectins, concanavalin A and Limax flavus agglutinin. Paraffin sections of the subcommissural organ and blots of subcommissural organ extracts have been analyzed. The ependymal cells of sectioned subcommissural organ are strongly stained with the antiserum. Concanavalin A binds to materials in all cytoplasmatic regions, whereas Limax flavus agglutinin identifies materials confined to the apex of the ependymal cells. In the blots, a band of 540 kDa is immunostained. This band is positive for concanavalin A positive but negative for Limax flavus agglutinin and is thereby regarded as representing a precursor form of the secretion.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 98
    ISSN: 1432-0878
    Keywords: Key words: Octopamine ; Nervous system ; central ; Immunocytochemistry ; Lumbricus terrestris (Annelida) ; Eisenia fetida (Annelida)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. The distribution of octopamine (OA)-like immunoreactive neurons was investigated, and the concentration of OA was assayed by high-performance liquid chromatography in the central nervous system of Oligochaeta species, Lumbricus terrestris, Eisenia fetida, and Lumbricus polyphemus. OA-like immunoreactive nerve cells were found in all parts of the central nervous system; certain regions of the neuropil of the ganglia were densely innervated by immunoreactive fibers. Altogether 96–102 OA-like immunoreactive neurons were detected in the cerebral ganglion, 18 in the subesophageal ganglion, and 14 in the segmental ganglia of 2nd–5th and 40th–45th body segments of Lumbricus terrestris; the relevant numbers of neurons in Eisenia were 88–98, 20–22, and 6, respectively. The sizes of OA immunoreactive-like cells showed great variability according to their anatomical localization. High-performance liquid chromatography assay revealed the presence of OA in each investigated part of the central nervous system, showing concentration values between 8.6 and 16.7 pmol/mg wet weight in the three species. The concentration of the OA precursor tyramine was significantly lower in the central nervous system of Eisenia (〈0.5 pmol/mg wet weight) than in that of both Lumbricus species (0.67–2.0 pmol/mg wet weight). The metabolism of 3H-tyrosine revealed that tyramine and OA were synthesized by the enzymes tyrosine-decarboxylase and tyramine-β-hydroxylase, respectively. Thus, OA appears to have a regulatory role in the central nervous system of Oligochaeta.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 99
    ISSN: 1432-1424
    Keywords: Water channels ; Vasopressin ; Rat kidney ; Immunocytochemistry ; Microtubules ; Cell polarity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Aquaporin 2 is a collecting duct water channel that is located in apical vesicles and in the apical plasma membrane of collecting duct principal cells. It shares 42% identity with the proximal tubule/thin descending limb water channel, CHIP28. The present study was aimed at addressing three questions concerning the location and behavior of the AQP2 protein under different conditions. First, does the AQP2 channel relocate to the apical membrane after vasopressin treatment? Our results show that AQP2 is diffusely distributed in cytoplasmic vesicles in collecting duct principal cells of homozygous Brattleboro rats that lack vasopressin. In rats injected with exogenous vasopressin, however, AQP2 became concentrated in the apical plasma membrane of principal cells, as determined by immunofluorescence and immunogold electron microscopy. This behavior is consistent with the idea that AQP2 is the vasopressin-sensitive water channel. Second, is the cellular location of AQP2 modified by microtubule disruption? In normal rats, AQP2 has a mainly apical and subapical location in principal cells, but in colchicine-treated rats, it is distributed on vesicles that are scattered throughout the entire cytoplasm. This is consistent with the dependence on microtubules of apical protein targeting in many cell types, and explains the inhibitory effect of microtubule disruption on the hydroosmotic response to vasopressin in sensitive epithelia, including the collecting duct. Third, is AQP2 present in neonatal rat kidneys? We show that AQP2 is abundant in principal cells from neonatal rats at all days after birth. The detection of AQP2 in early neonatal kidneys indicates that a lack of this protein is not responsible for the relatively weak urinary concentrating response to vasopressin seen in neonatal rats.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 100
    ISSN: 1435-604X
    Keywords: Heat shock protein 70 (hsp70) ; Carbon dioxide laser ; Sodium arsenite ; Human diploid fibroblast ; Electrophoresis ; Immunocytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Physics , Technology
    Notes: Abstract In a previous study, it was demonstrated that heat shock protein 70 (hsp70) was induced by short duration (〈1 s) carbon dioxide (CO2) laser radiation (10.6Μm. To further characterize the stress response after laser irradiation, the time course of synthesis and cellular localization of hsp70 has been followed. As it had been shown that laser irradiation elevated the temperature to about 67±2
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...