ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
Filter
  • Articles  (51)
  • Teleosts  (51)
  • Springer  (51)
  • American Geophysical Union (AGU)
  • American Meteorological Society
  • 1980-1984  (51)
  • 1935-1939
  • Medicine  (51)
Collection
  • Articles  (51)
Source
Keywords
Publisher
  • Springer  (51)
  • American Geophysical Union (AGU)
  • American Meteorological Society
Years
Year
Topic
  • 1
    Electronic Resource
    Electronic Resource
    The cellular envelope of oocytes in teleosts (1984)
    Springer
    Cell & tissue research 235 (1984), S. 403-410 
    Details
    ISSN: 1432-0878
    Keywords: Oocyte envelopes ; Folliculogenesis ; Vitello ; genin route ; Collagen-filled spaces ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Structural and functional relationships between oocytes and their envelopes were studied by means of electron microscopy in several teleost species after injection of live fish with horseradish peroxidase. The marker first appeared in the capillaries and the pericapillary spaces of the ovarian stroma. It then entered the collagen-filled spaces between the granulosa and theca cells; these spaces are in direct connection with the pericapillary spaces. The marker penetrated between the follicle cells and into the channels of the zona radiata surrounding the microvilli which traverse these channels. The marker was never found inside the microvilli or in the follicle cells; finally, it reached the surface of the oocytes and was internalized via micropinocytosis. Six stages in the course of folliculogenesis were observed, determined by (1) the formation of follicular and thecal cellular layers and a collagen-filled space between them, (2) the development of microvilli of oocytal and follicular origin, (3) the differentiation of the vitelline envelope and the pore channels, (4) pinocytotic activity of the oocytes, and (5) rapid growth of the oocyte and its envelopes during vitellogenesis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00217866
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Relationships between annulate lamellae and filament bundles in oocytes of the zebrafish, Brachydanio rerio (1984)
    Springer
    Cell & tissue research 236 (1984), S. 725-727 
    Details
    ISSN: 1432-0878
    Keywords: Annulate lamellae ; Microfilaments ; Filament bundles ; Polyribosomes ; Oocytes ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Bundles of filaments have been observed in the vitellogenic oocyte of the zebrafish, Brachydanio rerio; and these filaments illustrate a close spatial and structural relationship to annulate lamellae. The filaments range from 6–8 nm in diameter, and the annulate lamellae may cap both rounded ends of the bundle as well as extend parallel to the surface of the filament bundles. The ends of the filaments can be observed to exhibit an apparent termination in close relation to pore margins of the annulate lamellae, the membrane of the interpore regions of the annulate lamellae, as well as many nearby polyribosomes. The possible functional significance of this unique relationship is discussed in reference to a recent hypothesis regarding the function of annulate lamellae.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00217244
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Ultrastructure and immunolabeling of gonadotrops and thyrotrops in the pituitary of the African catfish, Clarias lazera (1984)
    Springer
    Cell & tissue research 238 (1984), S. 95-103 
    Details
    ISSN: 1432-0878
    Keywords: Pituitary gland, pars anterior (distalis) ; Gonadotrops ; Thyrotrops ; Ultrastructure ; Immunolabeling ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Pituitaries of the African catfish (Clarias lazera) were studied with immunocytochemical methods, at the light-microscopic and ultrastructural levels, for the characterization and localization of gonadotropic and thyrotropic cells. Two immunostaining procedures with the use of different markers were carried out: (i) with peroxidase-antiperoxidase, (ii) with protein A-gold. In routinely stained sections for light microscopy two types of basophils were identified in the proximal pars distalis: (1) large, round, purple cells, and (2) small, angular, light-blue cells. Both types were immunolabeled with antibodies against Clarias α,β-gonadotropin (GTH) and salmon G100-GTH. Only the large basophils were immunolabeled with anti-carp β-GTH, whereas the small basophils were the only cells immunolabeled with anti-human thyrotropin beta subunit (anti-h TSH-β). It was concluded that the large basophils represent the gonadotrops and the small basophils the thyrotrops. At the ultrastructural level the immunostaining of the GTH-cells was confined to three types of inclusions: (i) secretory vesicles, (ii) globules, and (iii) electron-dense, membrane-bound irregular masses. Especially the protein A- gold method, in combination with the use of a highly diluted homologous antiserum, resulted in a distinct localization of GTH. The presence of two types of nerve fibres, synaptically contacting the gonadotrops, is discussed with regard to the presence of a peptidergic (stimulatory) and an aminergic (inhibitory) control of GTH-secretion.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00215149
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Fine structure of monoamine-containing basal cells in the taste buds on the barbels of three species of teleosts (1984)
    Springer
    Cell & tissue research 235 (1984), S. 479-484 
    Details
    ISSN: 1432-0878
    Keywords: Monoamine-containing cells ; Taste bud ; Paracrine cells ; Mechanoreceptors ; Electron microscopy ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The taste buds on the barbels in three species of teleosts (Cyprinus carpio, Misgurnus anguillicaudatus, Parasilurus asotus) were studied by means of fluorescence and electron microscopy. Intensely yellow-fluorescent cells, which are disk-shaped and located exclusively in a basal position, are observed in the barbel-buds of all fishes examined. The basal cells contain a large number of small clear vesicles approximately 40–60 nm in diameter, which show a tendency to aggregate in the cytoplasm facing the junction of the nerve terminals; chemically transmitting synapses are seen in the latter region. It is suggested from the present observations that the basal cells in the barbel-bud may originate from Schwann cells and have a dual function both as mechanoreceptors and paracrine elements. Since the administration of 5,6-DHT results in an appearance of small dense vesicles among the small clear vesicles, the possibility exists that the basal cell may be capable of taking up monoamines and storing them in the small clear vesicles.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00226942
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Immunohistochemical localization of (neuro)peptide hormones in endocrine cells and nerves of the gut of a stomachless teleost fish, Barbus conchonius (Cyprinidae) (1984)
    Springer
    Cell & tissue research 237 (1984), S. 57-65 
    Details
    ISSN: 1432-0878
    Keywords: Enteroendocrine cells ; Innervation ; Neuropeptide immunocytochemistry ; Teleosts ; Gut hormones ; Intestine, small
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Enteroendocrine cells containing glucagon-, substance P-, neurotensin- and VIP-like substances have been demonstrated immunocytochemically in the gut of Barbus conchonius. Mainly based on the distribution of the immunoreactive endocrine cells in this and a previous* study, at least eight different enteroendocrine cell types appear to be present in this stomachless fish: 1. C-terminal-gastrinimmunoreactive cells*, predominantly present in the upper parts of the folds of the proximal part of the intestinal bulb. 2. Metenkephalin-immunoreactive cells*, basally located in the folds of the first segment. 3. Pancreatic polypeptide (PP)-immunoreactive cells*, mainly present in the first half of the first segment. 4. Glucagon-like-immunoreactive (GLI) cells that are basally located in the folds of the first segment and that contain a different polypeptide (possibly glicentin) than pancreatic glucagon cells. 5. Substance P-immunoreactive cells, present in the upper parts of the folds throughout the gut. 6. C-terminal-neurotensin-immunoreactive cells, basally located in the folds throughout the first segment. 7. Vasoactive intestinal polypeptide (VIP)-immunoreactive cells, present in small numbers in the proximal part of the intestinal bulb. 8. Nonspecifically-immunoreactive cells*, found throughout the intestinal bulb. Many VIP-immunoreactive nerves have been demonstrated in the smooth muscle layer and myenteric plexus of the gut; furthermore some of them are peptide histidineisoleucine (PHI)-immunoreactive. Substance P-, somatostatin-, neurotensin- and met-enkephalin-immunoreactive nerves are also found. Thus, at least partial sequences of four different mammalian neuropeptide hormones (VIP, substance P, neurotensin, met-enkephalin) occur both in endocrine cells and enteric nerves of the gut of B. conchonius.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00229200
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Regulation of cyclic nucleotides in retinal photoreceptors (1984)
    Springer
    Cell & tissue research 237 (1984), S. 95-101 
    Details
    ISSN: 1432-0878
    Keywords: Visual system ; Photoreceptor cells ; cAMP ; cGMP ; Adenylate cyclase ; Guanylate cyclase ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The distribution of cyclases in retinal photoreceptors of dark- and light-adapted brook trout was studied by means of a cytochemical method (lead precipitation). It confirms earlier reports that retinal photoreceptors contain high levels of cyclic nucleotides, and that cAMP predominates in cones and cGMP in rods. There is an apparent difference in the level of the cyclases with the adaptive states. In addition, the catalytic unit of cyclase is interlamellar in cones. In rods, adenylate cyclase is intradiscal, while the location of guanylate cyclase varies with the adaptive state. The variation of cyclase with adaptation indicates that this enzyme has a role in the process of visual transduction.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00229203
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Changes in metabolism and hepatic ultrastructure induced by estradiol and testosterone in immature female Epinephelus akaara (Teleostei, Serranidae) (1984)
    Springer
    Cell & tissue research 236 (1984), S. 651-659 
    Details
    ISSN: 1432-0878
    Keywords: Steroids ; Vitellogenesis ; Metabolism ; Ultrastructure ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Estradiol injections increase serum level of calcium, amino acid, glucose, protein, ammonia and creatinine in immature Epinephelus akaara, and also increase levels of total lipid, cholesterol, phospholipid and esterified fatty acids. Hepatic protein, glycogen and lipid concentrations also rise after estradiol treatment, and some hepatic enzymes participating in the metabolism of nitrogen, lipid and carbohydrate, show increased activity. Serum vitellogenin levels are increased. Testosterone treatment increases serum protein, total lipid, cholesterol, amino acid and ammonia levels, and also hepatic glycogen content, but in contrast to estradiol treatment, testosterone does not change serum vitellogenin, glucose, calcium, phospholipid, esterified fatty acid and creatinine levels, nor the hepatic lipid and protein content. A small number of hepatic enzymes shows an increased activity. Vitellogenic fish show biochemical changes similar to that of estradiol-treated fish, but are different from those of immature fish. Estradiol treatment induces ultrastructural changes in the hepatocytes of immature fish that are similar to those found in vitellogenic fish. These include a proliferation of rough endoplasmic reticulum and Golgi apparatus, and an increase in glycogen and lipid, all indicative of enhanced metabolic activity.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00217235
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Immunocytochemical identification of CRF-like and SRIF-like peptides in the brain and the pituitary of cyprinid fish (1984)
    Springer
    Cell & tissue research 237 (1984), S. 379-382 
    Details
    ISSN: 1432-0878
    Keywords: Corticotropin-releasing factor (CRF) ; Soma-ostatin (SRIF) ; Brain ; Preoptic nucleus ; Pituitary gland ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Single and double immunocytochemical techniques were applied to the brain and pituitary of carps and goldfish. With the use of antiserum raised against synthetic corticotropin-releasing factor (CRF), immunoreactive perikarya were observed in the nucleus praeopticus and the nucleus praeopticus periventricularis. CRF-like-immunoreactive hypothalamic nerve fibers reach the pituitary. In cyprinids, some fine fibers enter the rostral neurohypophysis bordered by prolactin- and ACTH cells. Other thicker fibers extend ventrocaudally into the neurointermediate lobe. This CRF-like system appears to differ from the SRIF-like system, which is restricted to the proximal pars distalis of the pituitary containing somatotrophs.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00217162
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Ultrastructure and adrenergic innervation of preglomerular arterioles in the euryhaline teleost, Salmo gairdneri (1984)
    Springer
    Cell & tissue research 237 (1984), S. 451-458 
    Details
    ISSN: 1432-0878
    Keywords: Kidney ; Adrenergic innervation, renal ; Renal vasculature ; Preglomerular sphincter ; Glomerulus, filtration ; Microcirculation ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The opisthonephric kidney of the rainbow trout was investigated by light- and electron microscopy and a fluorescent-histochemical technique for biogenic amines was used. Preglomerular sphincters at the origin of afferent arterioles are present in this euryhaline teleost. The branching point of the afferent arteriole is characterized by (i) the formation of a right angle with the parent vessel, (ii) circularly arranged smooth muscle cells of the tunica media, (iii) additional circularly arranged smooth muscle cells intercalated between endothelium and tunica media, and (iv) a collar-like arrangement of several large endothelial cells with elaborate marginal folds and abundant myoendothelial junctions. A dense adrenergic innervation displaying specific fluorescence was found along the terminal arterioles and afferent arterioles, and conspicuously at the preglomerular sphincters. These results are suggestive of a neural participation in kidney function. They are discussed on the basis of recent evidence from pharmacological and physiological experiments for neural involvement in glomerular intermittency.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00228429
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    The blood-testis barrier in Aphanius dispar (Teleostei) (1980)
    Springer
    Cell & tissue research 211 (1980), S. 207-214 
    Details
    ISSN: 1432-0878
    Keywords: Blood-testis barrier ; Sertoli cell ; Myoid cell ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Thin sections of normal testes from the cyprinodont Aphanius dispar were studied by electron microscopy after intravascular injection of live specimens with horseradish peroxidase. The intercellular space in the spermatogenic cysts is marked differently by the tracer according to the degree of differentiation of the germ cells. Spermatogonia and gonocytes undergoing meiosis are surrounded by a dark band of the marker. This band gradually disappears during spermiogenesis. In cysts containing ripe spermatozoa, the marker penetrates a short distance between the bases of adjoining Sertoli cells bordering the cysts, but is arrested by tight junctional complexes near the lumina of the cysts. The tight junctions between the Sertoli cells provide a permeability barrier between the vascular spaces of the stroma and the lumina of ripe cysts.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00236443
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 11
    Electronic Resource
    Electronic Resource
    Vasoactive intestinal polypeptide-like immunoreactivity in nerves of the pancreatic islet of the teleost fish, Gillichthys mirabilis (1980)
    Springer
    Cell & tissue research 212 (1980), S. 139-146 
    Details
    ISSN: 1432-0878
    Keywords: Endocrine pancreas ; Innervation ; Teleosts ; Peptides ; Vasoactive intestinal polypeptide (VIP)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In the teleost fish, Gillichthys mirabilis, vasoactive intestinal polypeptide (VIP)-like immunoreactivity is present in some nerve fibres of the principal pancreatic islet and surrounding tissues, the vagus and splanchnic nerves, the coeliac ganglion and the wall of the intestine. The nerves of the pancreatic islet that contain VIP-like immunoreactivity probably correspond to one of the two types of non-cholinergic, non-adrenergic (peptidergic) nerve previously described in this fish. Similarities in the localisation of hormonal peptides in fish and mammals suggest that the regulation of gastroenteropancreatic physiology in fish may resemble that of mammals.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00234040
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 12
    Electronic Resource
    Electronic Resource
    Somatostatin in the brain and the pituitary of some teleosts (1984)
    Springer
    Cell & tissue research 238 (1984), S. 289-296 
    Details
    ISSN: 1432-0878
    Keywords: Somatostatin (SRIF) ; Brain ; Pituitary gland ; Immunocytochemistry ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Immunocytochemical investigations show that somatostatin (SRIF)-like immunoreactive material is present in the brain and the pituitary of nine different species of teleosts. In the brain, immunoreactive perikarya and fibers are observed in the preoptic periventricular nucleus, the entopeduncular nucleus, the anterior periventricular nucleus, and the nucleus lateralis tuberis. In the pituitary, SRIF-like-immunoreactive fibers occur in the proximal pars distalis (PPD), which contains the growth hormone (GH)-secreting cells. Nerve fibers are scattered among GH cells (cyprinids), or end on the basal lamina at the neuroglandular interface of the PPD (eel, salmonids). In the eel, the proximal neurohypophysis does not penetrate deeply into the PPD that is very poorly vascularized. In some species, e.g. Myoxocephalus, SRIF-like immunoreactive fibers are also observed in the caudal neurohypophysis, and even among MSH cells of the pars intermedia. In long-term starved carps and eels, the amount of SRIF-like material in the pituitary is clearly reduced. A possible role of SRIF in the concomitant stimulation of GH cells is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00217300
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 13
    Electronic Resource
    Electronic Resource
    Topography of retinal axons in the diencephalon of goldfish (1984)
    Springer
    Cell & tissue research 238 (1984), S. 529-538 
    Details
    ISSN: 1432-0878
    Keywords: Hypothalamus ; Thalamus ; Visual centers ; Horseradish-peroxidase histochemistry ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The projections of horseradish peroxidase-filled axons from each quadrant of the retina were studied to determine whether retinal projections of goldfish are topographically organized in diencephalic target nuclei. A distinct topography of the dorsal, nasal, ventral and temporal retina exists in the lateral geniculate nucleus and in the dorsolateral optic nucleus of the thalamus. The projections of retinal quadrants show minimal spatial overlap in each of these nuclei. The suprachiasmatic nucleus of the hypothalamus is extensively innervated by ventral retinal fibers, whereas the nucleus is sparsely innervated by fibers from the other three retinal quadrants. A rudimentary topography also exists in the pretectum where the dorsal pretectal area receives projections primarily from the ventral retina and the ventral pretectal area receives projections mostly from the dorsal retina. These data show that retinal projections to some diencephalic nuclei are topographically organized.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00219869
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 14
    Electronic Resource
    Electronic Resource
    PAS-positive cells of the pars intermedia are calcium-sensitive in the goldfish maintained in a hyposmotic milieu (1980)
    Springer
    Cell & tissue research 212 (1980), S. 29-38 
    Details
    ISSN: 1432-0878
    Keywords: Pituitary ; Pars intermedia ; Calcium ; Deionized water ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Cytological changes in the pars intermedia of the goldfish were investigated after adding calcium to deionized water (DW). In fish maintained in DW, the PAS-positive cells are highly stimulated in comparison to cells of fish kept in fresh water (FW). In DW supplemented with calcium at the same concentration as in FW (2 mM/l), the hyperactivity of the PAS-positive cells is prevented. When calcium ions are added 60 h before the animals are sacrificed, the PAS positive cells start to show signs of regression and their granules are stored: the release of the granular material appears to be suppressed by calcium. In the goldfish, the PAS-positive cells, homologous to a similar cell type in the eel, react only very weakly with the PAS technique. The name “calcium-sensitive cells” appears to be more appropriate in the goldfish for this particular cell type, secreting an unknown factor. This factor, different from the prolactin produced in the rostral pars distalis of the hypophysis, might be an equivalent of a “hypercalcin”.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00234030
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 15
    Electronic Resource
    Electronic Resource
    Response of prolactin cells to environmental calcium in the eel (Anguilla anguilla L.) (1983)
    Springer
    Cell & tissue research 229 (1983), S. 243-252 
    Details
    ISSN: 1432-0878
    Keywords: Pituitary ; Prolactin cells ; Teleosts ; Calcium regulation ; Sodium regulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Prolactin (PRL) cell activity was investigated in eels kept in fresh water (FW), deionized water (DW) supplemented or not with Ca (2 mM), in Ca-enriched FW (10 mM), in normal (Ca 3.4 mM) or Ca-free 1/3 sea water (SW), and in SW (Ca 10.2 mM) or Ca-free SW (Ca 0.15 mM). Light-microscopic studies, including measurement of the nuclear area and cell height, showed that PRL cell activity, reduced in DW, is not affected by Ca supplementation. Activity is reduced in Ca-enriched FW, in 1/3 SW and in SW, conditions inducing an increase in the plasma sodium level. The lack of calcium in saline environments partly suppresses the nuclear atrophy occurring in SW. There is no significant correlation between external or total plasma calcium concentration and PRL cell activity. In artificial Ca-free SW, eels show a rapid increase in plasma osmolarity and sodium levels; there is a significant negative correlation between these two plasma values and the nuclear area or cell height of PRL cells. As in some other teleosts, plasma osmolarity and plasma sodium seem to play a more important role than external or internal calcium in controlling PRL secretion. This correlation is not apparent in eels kept in DW, having unstimulated PRL cells but active calcium-sensitive (Ca-s) cells in the pars intermedia.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00214973
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 16
    Electronic Resource
    Electronic Resource
    Calcium-sensitive cells of the pars intermedia and osmotic balance in the eel (1982)
    Springer
    Cell & tissue research 225 (1982), S. 487-496 
    Details
    ISSN: 1432-0878
    Keywords: Pituitary ; Intermediate lobe ; Calcium-sensitive (PAS-positive) cells ; Teleosts ; Osmoregulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Freshwater eels were adapted to calcium-free sea water (SW) or 1/3 Ca-free SW. Survival was generally poor in Ca-free SW, although three eels were still in good condition after 19–30 days; survival in 1/3 Ca-free SW was excellent. Osmotic disturbances (increase of plasma osmolarity and sodium levels), which initially occur in Ca-free SW, were no longer detectable after 19–30 days, or in eels in 1/3 Ca-free SW after one month. Plasma calcium sharply decreases initially; it is less depressed after 19–30 days and in 1/3 Ca-free SW. Alterations in the mucus production may be involved in the osmotic changes. Under these conditions no clear stimulation of the calcium-sensitive (Ca-s) cells of the pars intermedia was registered, but in Ca-free SW (1/3 or full strength) the inhibitory effect normally observed in SW does not occur. In a hyperosmotic environment, other ion(s), possibly magnesium, may reduce the response of the Ca-s cells to a lack of environmental calcium.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00214799
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 17
    Electronic Resource
    Electronic Resource
    Routine oxygen consumption and characteristics of the myotomal muscle in tench: Effects of long-term acclimation to hypoxia (1982)
    Springer
    Cell & tissue research 227 (1982), S. 161-177 
    Details
    ISSN: 1432-0878
    Keywords: Skeletal muscle ; Respiration ; Hypoxia ; Vascularisation ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Tench (Tinca tinca) were acclimated to either aerated (P O 2 17.6 KPa) or hypoxic water (P O 2 1.5 KPa) at 15° C. Fish acclimated to P O 2 17.6 KPa had a routine oxygen consumption (mls O2/Kg bodyweight/h) of 32.7 in aerated water. Upon acute exposure to P O 2 1.5 KPa oxygen consumption decreased to 10.8 and 15.6 in fish acclimated to aerated and hypoxic water, respectively. On the basis of staining for glycogen and for the activities of myofibrillar ATPase and succinic dehydrogenase, three main fibre types can be differentiated in the myotomal muscle. Fibres have been classified as slow, fast aerobic and fast glycolytic. Fast aerobic fibres can be distinguished histochemically by their alkaline-stable Ca2+-activated myofibrillar ATPase activity and their intermediate levels of staining for glycogen and succinic dehydrogenase activity. The patterns of innervation of the fibre types have been investigated by staining neuromuscular endplates and peripheral axons for acetylcholinesterase activity. Motor axons to slow fibres branch extensively giving rise to a number of diffuse endplate formations on the same and adjacent fibres. Fast glycolytic fibres also have a complex pattern of innervation with 8–20 endplates per fibre. A large proportion of the endplates belonged to separate axons. Cross-sectional areas and perimeters of fibres, the number of capillaries/fibre and the lengths of contacts between capillaries and fibres were determined from low-magnification electron micrographs. Acclimation to hypoxia resulted in a decrease in the number of capillaries per fibre for both slow (1.8 to 1.0) and fast (0.8 to 0.2) muscles. The capillary perimeter supplying 1 μm2 of fibre cross-sectional area decreased by 43 % and 76 % for slow and fast fibres, respectively.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00206339
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 18
    Electronic Resource
    Electronic Resource
    Ultrastructure and metabolism of skeletal muscle fibres in the tench: Effects of long-term acclimation to hypoxia (1982)
    Springer
    Cell & tissue research 227 (1982), S. 179-199 
    Details
    ISSN: 1432-0878
    Keywords: Hypoxia acclimation ; Muscle ultrastructure ; Liver ; Metabolism ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Tench (Tinca tinca) were acclimated to either aerated (P O 2 17.6 KPa) or hypoxic (P O 2 1.5 KPa) water for 6 weeks. Acclimation to hypoxia resulted in a decrease in mitochondrial volume fraction in both slow (22.9 to 15.0 %) and fast glycolytic (4.5 to 1.8 %) myotomal muscles fibres (P〈0.01). Intermyofibrillar mitochondrial populations (4.4 to 1.2% slow; 0.6 to 0.04% fast fibres) were affected to a greater extent than those in the subsarcolemmal zone (18.5 to 13.8% slow; 3.9 to 1.8% fast fibres). After acclimation to hypoxia, cytochrome-oxidase activities decreased by 31 and 33 % in slow and fast fibres, respectively, but were maintained in the liver. Fibre size remained unchanged and actively differentiating fibres were observed in muscles from both groups of fish. Hypoxia resulted in a significant increase in myofibrillar volume fraction in both slow (43.1 to 56.1 %) and fast glycolytic fibres (73.1 to 82.7%) (P〈0.05). Glycogen concentrations (mg/100g tissue) for liver (6616) slow muscle (1892) and fast muscle (334) were similar for fish acclimated to aerated or hypoxic water. Acclimation to hypoxia increased carnitine palmitoyl transferase activity (μmoles substrate utilised g·dry wt-1 min-1) in slow (0.42 to 1.1), fast glycolytic muscle (〈0.01 to 0.15) and liver (1.1 to 3.7) indicating an enhanced capacity for fatty acid oxidation. Phosphofructokinase activities of fast glycolytic fibres were similar in fish acclimated to either aerated or hypoxic water, consistent with an unaltered capacity for anaerobic glycogenolysis. Hexokinase activities (μmoles substate utilised, g·dry wt-1 min-1) decreased in fast fibres (1.2 to 0.4) but were maintained in the slow muslce (2.1 to 2.5) and liver (4.5 to 4.8) of hypoxic fish. The activities of phosphofructokinase in slow muscle and phosphofructokinase, pyruvate kinase and lactate dehydrogenase in liver were two times higher in fish acclimated to hypoxia. An enhanced capacity for glycolysis in these tissues may reflect a reduced threshold for anaerobic metabolism during activity and/or an adaptation for acute exposure to anoxia in fish acclimated to hypoxia.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00206340
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 19
    Electronic Resource
    Electronic Resource
    Ultrastructure of the “smooth endoplasmic reticulum cell” in the nucleus recessus lateralis of Salmo gairdneri Richardson (1982)
    Springer
    Cell & tissue research 227 (1982), S. 221-224 
    Details
    ISSN: 1432-0878
    Keywords: Hypothalamus ; Nucleus recessus lateralis ; Smooth endoplasmic reticulum ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The fine structure of one of the cellular components of the nucleus recessus lateralis of trout is described. These cells have an enormously developed smooth endoplasmic reticulum which makes their identification easy. The relationship of this cell type with the ventricular cavity, neighbouring cells and the presence of synaptic contacts with these cells are also described.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00206343
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 20
    Electronic Resource
    Electronic Resource
    Histophysiological and immunocytochcmical study on the nature of the thyrotrops in the pituitary of immature rainbow trout, Salmo gairdneri (1983)
    Springer
    Cell & tissue research 231 (1983), S. 185-198 
    Details
    ISSN: 1432-0878
    Keywords: Thyroid ; Pituitary ; Thyrotrops ; Gonadotrops ; Immunocytochemistry ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Alcian blue and periodic acid-Schiff-positive “granular basophils” with electron-dense granules ±160 nm in diameter, and weakly developed irregular cisternae of the granular endoplasmic reticulum (GER) are present in the rostral pars distalis (RPD) and the proximal pars distalis (PPD) of immature rainbow trout. They all react with antisalmon αβ-gonadotropin. However, only granular basophils in the caudal RPD and the rostro-dorsal PPD, often bordering on and sometimes surrounded by neurohypophysial tissue, react with anti-human β-TSH. These cells, considered as the source of thyrotropin, show degranulation and dilatation of the GER-cisternae in fish treated with potassium perchlorate. The thyroids of the goitrogen-treated animals had relatively numerous small follicles with a high epithelium. The remaining granular basophils are gonadotrops.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00215785
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 21
    Electronic Resource
    Electronic Resource
    Evidence for 5-HT-containing intrinsic neurons in the teleost intestine (1983)
    Springer
    Cell & tissue research 230 (1983), S. 377-386 
    Details
    ISSN: 1432-0878
    Keywords: Intestine ; Teleosts ; 5-HT ; Enteric neurons
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The stomach and small intestine of seven species of teleost fish were examined with both fluorescence and ultrastructural histochemical techniques for demonstrating monoamines. Fluorescence histochemistry demonstrated large numbers of yellow fluorescent neurons in the myenteric plexus of the intestine, but not the stomach, of four species. Varicose fibres arising from these neurons ran in the myenteric plexus, circular muscle layer and submucosa. Ultrastructural histochemistry of tissue fixed with a modified chromaffin reaction showed that some neurons in the myenteric plexus contained biogenic amines in vesicles of 40–100 nm diameter. It is concluded that 5-HT-containing neurons are present in the intestine of some teleost species.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00213811
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 22
    Electronic Resource
    Electronic Resource
    CSF-contacting and other somatostatin-immunoreactive neurons in the brains of Anguilla anguilla, Phoxinus phoxinus, and Salmo gairdneri (Teleostei) (1983)
    Springer
    Cell & tissue research 233 (1983), S. 319-334 
    Details
    ISSN: 1432-0878
    Keywords: CSF-contacting neurons ; Somatostatin immunocytochemistry ; Hypothalamus ; Entopeduncular nucleus ; Pretectal area ; Tegmentum ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A system of somatostatin-immunoreactive neurons was demonstrated in the brains of the eel, Anguilla anguilla, the European minnow, Phoxinus phoxinus, and the rainbow trout, Salmo gairdneri, by means of the light-microscopic indirect immunoperoxidase technique. In the anterior periventricular nucleus, somatostatin-immunoreactive cerebrospinal fluid (CSF)-contacting neurons display intensely stained intraventricular dendritic protrusions, perikarya, and axonal processes. The latter taper into a somatostatin-immunoreactive fiber plexus extending to the infundibulum, the proximal neurohypophysis, and the lateral and mammillary recesses. In addition, somatostatin-immunoreactive neurons were demonstrated in the magnocellular preoptic, entopeduncular and dorsolateral thalamic nuclei, further in the pretectal area and the ventrolateral tegmentum. Somatostatin-immunoreactive fiber bundles project via the stria medullaris toward the habenular nucleus; they also course in the dorsomedial-ventrolateral direction at the level of the pretectal-tegmental area, and within the ventral and dorsal tegmentum. The presence of somatostatin in a variety of different neurons of the teleost brain is discussed in connection with their tentative inhibitory function. The CSF-contacting neurons of the anterior periventricular nucleus are supposed to function as sensors that pass information from the CSF to the somatostatin system of the hypothalamus and/or other components of the neuroendocrine apparatus.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00238299
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 23
    Electronic Resource
    Electronic Resource
    Changes in glomerular structure after sexual maturation and seawater adaptation in males of the euryhaline teleost Gasterosteus aculeatus L. (1980)
    Springer
    Cell & tissue research 206 (1980), S. 1-20 
    Details
    ISSN: 1432-0878
    Keywords: Kidney ultrastructure ; Teleosts ; Seawater adaptation ; Sexual maturation ; Glomerular filtration barrier
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In sexually mature male sticklebacks, the renal tubular cells are transformed from ion reabsorbing to mucus secreting cells and in these fish concomitant changes take place in the glomeruli. The present study compares glomerular structure of immature males in fresh water (controls) to those of mature males in fresh water and to immature male sticklebacks in seawater. Glomerular structure is markedly altered in the latter two groups and the changes are similar to a large extent. In these two groups the renal capsules and glomeruli are smaller and the lumina of the glomerular capillaries decrease in diameter, while the number and size of the endothelial fenestrations are reduced. Mesangial cells proliferate and the mesangial matrix greatly expands in both the centrolobular region and the subendothelial space around the capillaries. The secretory activity of the podocytes is enhanced and is responsible for the observed increase in thickness of the outer layer of the basal lamina, the lamina rara externa. The area covered by the filtration slit membranes is reduced, probably as a consequence of fusion of the pedicels of the podocytes. The permeability characteristics of the glomerular filtration barrier for macromolecules, as studied with ferritin injections, remain unaltered. However, the observed differences point to a reduction of the glomerular filtration rate (GFR) during maturation in male sticklebacks, as well as during adaptation of sticklebacks to seawater. This conclusion is in line with physiological evidence.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00233603
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 24
    Electronic Resource
    Electronic Resource
    Responses of MSH and prolactin cells to 5-hydroxytryptophan (5-HTP) in amphibians and teleosts (1980)
    Springer
    Cell & tissue research 207 (1980), S. 377-385 
    Details
    ISSN: 1432-0878
    Keywords: Serotonin ; MSH ; Prolactin ; Teleosts ; Amphibians
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Injection of 5-hydroxytryptophan (5-HTP), a precursor of serotonin, induces dispersion of melanin in the amphibians, Pleurodeles waltlii (Urodela) and Xenopus laevis (Anura), in the goldfish, Carassius auratus, and in the carp, Cyprinus carpio. It is accompanied by a dispersion of erythrophore pigments. In the pituitaries of Pleurodeles and goldfish, a stimulation of MSH cells, characterized by a significant nuclear hypertrophy, is also observed; in Carassius, MSH cells may become degranulated. Serotonin appears to exert a stimulating effect on MSH release in lower vertebrates. Swimming behavior is disturbed in the goldfish and the carp; gaseous metabolism in the swim-bladder may be affected by injection of 5-HTP, as previously reported in the eel. Prolactin (PRL) cells appear activated, but remain granulated in the treated goldfish. No clear response of PRL cells to injection of 5-HTP can be observed in Pleurodeles. A possible role of serotonin in Pleurodeles submitted to an experimental aeroionization is briefly discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00224614
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 25
    Electronic Resource
    Electronic Resource
    Regeneration of spinal electrocyte fibers in Sternarchus albifrons: Development of axon-schwann cell relationships and nodes of Ranvier (1980)
    Springer
    Cell & tissue research 208 (1980), S. 343-352 
    Details
    ISSN: 1432-0878
    Keywords: Axons ; Regeneration ; Schwann cells ; Spinal cord ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The electrocyte fibers in the gymnotid Sternarchus albifrons are highly differentiated myelinated axons which exhibit several types of nodes of Ranvier and characteristically short internode lengths. In the present study, regeneration of the electrocyte fibers following removal of the tail was examined by electron microscopy. By 36 days following extirpation, the regenerating electrocyte axons exhibit Type I nodes of Ranvier, with a normal morphology, and Type II nodes of Ranvier with a large nonmyelinated gap and a polypoid elaboration of the axon surface. Moreover, in the regenerating axons the internode length ∶ diameter ratios are quite small. Thus, relatively normal axon-Schwann cell relations and a relatively normal differentiation of the axon surface are achieved during regeneration of the Sternarchus electrocyte fibers.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00233869
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 26
    Electronic Resource
    Electronic Resource
    Responses of the teleost pituitary (goldfish, eel) to deionized water (1980)
    Springer
    Cell & tissue research 208 (1980), S. 389-404 
    Details
    ISSN: 1432-0878
    Keywords: Pituitary ; Prolactin ; Pars intermedia ; Deionized water ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The cytological responses of the pituitary gland during adaptation to deionized water (DW) were investigated in the goldfish and the eel. In both teleost species, a stimulation of the prolactin (PRL) cells could not be detected, although the levels of blood electrolytes (Na+,Ca2+,Cl−) are reduced in the eel. PRL cells appear less active in DW-adapted eels. A striking stimulation of the PAS-positive cells of the pars intermedia occurs in both species after 3 weeks and, in the eel, is still present after 11 weeks. Cell and nuclear hypertrophy, mitoses and a well-developed endoplasmic reticulum are observed. MSH cells are partially degranulated when pigmentation is affected; a reduced activity of MSH cells is evident after 11 weeks. The amount of neurohypophysial tissue is reduced. In the goldfish and the eel, during adaptation to DW, an unknown factor secreted by the PAS-positive cells of the pars intermedia appears to play a more important role than the secretion of PRL. These two species are able to survive in fresh water without the pituitary. The control of the PAS-positive cells by external sodium or calcium is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00233872
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 27
    Electronic Resource
    Electronic Resource
    Bilateral retinal projections in the black piranah (Serrasalmus niger) (1980)
    Springer
    Cell & tissue research 213 (1980), S. 483-495 
    Details
    ISSN: 1432-0878
    Keywords: Visual system ; Thalamus ; Optic tectum ; Teleosts ; Autoradiography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The retinal projections were studied in the black piranah (Serrasalmus niger) with degeneration and autoradiographic methods. The projections are bilateral to the hypothalamic optic nucleus, the dorsomedial optic nucleus, corpus geniculatum ipsum of Meader (1934) and the optic tectum. Unilateral, crossed projections were traced to the pretectal nucleus and the cortical nucleus. The visual system of the black piranah is exceptionally well developed but has retained many primitive features including the extensive bilateral projections.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00237893
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 28
    Electronic Resource
    Electronic Resource
    Ultrastructural changes in the calcium-sensitive (PAS-positive) cells of the pars intermedia of eels kept in deionized water and in normal and concentrated sea water (1981)
    Springer
    Cell & tissue research 219 (1981), S. 9-26 
    Details
    ISSN: 1432-0878
    Keywords: Pituitary ; Intermediate lobe ; Calcium-sensitive (PAS-positive) cells ; Teleosts ; Osmoregulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of the calcium-sensitive (Ca-s) (PAS-positive) cells of the pars intermedia was investigated in eels kept in hypo and hyperosmotic environments. Although the cells were moderately active in fresh water (FW), they were highly stimulated in deionized water (DW) and displayed an enlarged Golgi apparatus, a distinct rough endoplasmic reticulum, few secretory granules, some microtubules and an extended area of contact with the basal lamina that separates nervous and glandular tissues. Some mitosing cells were seen. A similar picture was observed in eels kept in sea water (SW) for 45 days, returned to FW and subsequently to DW for 21 days. In SW (30 and 33‰), and particularly in concentrated SW (50, 60 and 63‰), the Ca-s cells were inactive. Their granules were significantly smaller than in eels kept in FW, and the area of contact with the basal lamina was greatly reduced. However, signs of granule-release were seen in eels adapted to 50 and 60‰ SW. Nerve fibers rarely contacted the Ca-s cells and did not synapse with them. The ultrastructural data support the hypothesis that the Ca-s cells of Anguilla, like those of Carassius, are involved in ionic regulation. MSH cells were not greatly affected by the present experiments.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00210015
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 29
    Electronic Resource
    Electronic Resource
    Fine structure and metabolism of multiply innervated fast muscle fibres in teleost fish (1981)
    Springer
    Cell & tissue research 219 (1981), S. 93-109 
    Details
    ISSN: 1432-0878
    Keywords: Quantitative cytology ; Fish muscle ; Muscle metabolism ; Muscle ultrastructure ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Both the fast and slow muscle fibres of advanced teleost fish are multiply innervated. The fraction of slow-fibre volume occupied by mitochondria is 31.3%, 25.5% and 24.6%, respectively, for the myotomal muscles of brook trout (Salvelinus fontinalis), crucian carp (Carassius carassius), and plaice (Pleuronectes platessa), respectively. The corresponding figures for the fast muscles of these species are 9.3%, 4.6% and 2.0%, respectively. Cytochrome-oxidase and citrate-synthetase activities in the fast muscles of 9 species of teleost range from 0.20–0.93 μmoles substrate utilised, g wet weight muscle-1 min-1 (at 15° C) or around 4–17% of that of the corresponding slow fibres. Ultrastructural analyses reveal a marked heterogeneity within the fast-fibre population. For example, the fraction of fibres with 〈1% or 〉10% mitochondria is 0,4,42% and 36, 12 and 0%, respectively, for trout, carp and plaice. In general, small fibres (〈500 μm2) have the highest and large fibres (〉1,500 μm2) the lowest mitochondrial densities. The complexity of mitochondrial cristae is reduced in fast compared to slow fibres. Hexokinase activities range from 0.4–2.5 in slow and from 0.08–0.7 μmoles, g wet weight-1 min-1 in fast muscles, indicating a wide variation in their capacity for aerobic glucose utilisation. Phosphofructokinase activities are 1.2 to 3.6 times higher in fast than slow muscles indicating a greater glycolytic potential. Lactate dehydrogenase activities are not correlated with either the predicted anaerobic scopes for activity or the anoxic tolerances of the species studied. The results indicate a considerable variation in the aerobic capacities and principal fuels supporting activity among the fast muscles of different species. Brook trout and crucian carp are known to recruit fast fibres at low swimming speeds. For these species the aerobic potential of the fast muscle is probably sufficient to meet the energy requirements of slow swimming.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00210021
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 30
    Electronic Resource
    Electronic Resource
    Testosterone-dependent changes in vivo and in vitro in the structure of the renal glomeruli of the teleost Gasterosteus aculeatus L. (1981)
    Springer
    Cell & tissue research 219 (1981), S. 253-266 
    Details
    ISSN: 1432-0878
    Keywords: Kidney (stickleback) ; Teleosts ; Glomerulus ; Testosterone (effect of) ; Organ culture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary During the reproductive period of the male stickleback, structural and functional changes of the kidney take place, both in the glomeruli and in the renal tubule cells. The structural changes in the glomeruli involve almost all glomerular components and point to a reduction of the glomerular filtration rate. The purpose of this study was to investigate whether these changes are controlled by testosterone, indirectly or directly. In vivo experiments demonstrated that exposure of immature castrates for 8 days to methyltestosterone leads to activation of mesangial cells and podocytes, to slight expansion of mesangial matrix and slight thickening of basal lamina. Observations on cultured renal tissue showed that two androgens, 11-ketotestosterone and methyl testosterone, are also able to stimulate the secretory activity of podocytes and mesangial cells in vitro. The results therefore indicate, that most glomerular changes in male sticklebacks during the reproductive season are directly effected by testosterone.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00210146
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 31
    Electronic Resource
    Electronic Resource
    Optic tract cells projecting to the retina in the teleost, Pantodon buchholzi (1982)
    Springer
    Cell & tissue research 225 (1982), S. 23-28 
    Details
    ISSN: 1432-0878
    Keywords: Visual system ; Retino-petal pathways ; HRP method ; Optic tract ; Pantodon buchholzi ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Horseradish peroxidase was employed to trace retino-fugal and retino-petal connections in the teleost fish, Pantodon buchholzi. Most of the reciprocal connections found were within the range also observed in previously studied species of teleosts. Of particular interest is the discovery of cells located within the optic tract and projecting to the retina. These neurons were investigated electron microscopically.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00216215
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 32
    Electronic Resource
    Electronic Resource
    Immunocytochemical devidence for hypophysial projections of the cells of the nucleus lateralis tuberis pars lateralis in the rainbow trout (Salmo gairdneri) (1983)
    Springer
    Cell & tissue research 228 (1983), S. 43-50 
    Details
    ISSN: 1432-0878
    Keywords: Nucleus lateralis tuberis ; Hypothalamo-hypophysial relationship ; Immunocytochemistry ; Prolactin cells ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In the rainbow trout the pars lateralis is the most prominent part of the nucleus lateralis tuberis (NLT). To demonstrate a morphological relationship between this lateral part of the NLT and the pituitary, immunocytochemistry was applied as a staining method. Experiments were carried out on glutaraldehyde-picric acid-acetic acidfixed brain sections of mature male and female rainbow trout using the peroxidase-anti-peroxidase immune technique with an antiserum against 27-S-methylglucagon as the first antibody. Most of the cells in the NLT/pars lateralis reacted with the antiserum. Axons from these cells enter the pituitary, extending exclusively in the numerous neurohypophysial digitations in the pars intermedia. No immunoreactive neurohypophysial protrusions were found in those parts of the adenohypophysis where the gonadotropic cells are located, indicating that the lateral part of the NLT is not directly involved in the control of gonadotropin secretion. In addition to cells of the NLT/pars lateralis only prolactin cells in the rostral pars distalis of the adenohypophysis reacted with the antiserum used.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00206263
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 33
    Electronic Resource
    Electronic Resource
    Ingrowth of optic nerve fibers and onset of myelin ensheathment in the optic tectum of the trout (Salmo gairdneri) (1982)
    Springer
    Cell & tissue research 227 (1982), S. 201-211 
    Details
    ISSN: 1432-0878
    Keywords: Optic systems ; Axonal growth ; Myelination ; Ultrastructure ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The early differentiation of the optic pathway of the trout was studied by means of autoradiography, silver impregnation and electron microscopy. Ingrowth of optic nerve fibers into the optic tectum was consistently shown by tracer application and Golgi studies to occur at stage 28, about one week before hatching. Fibers being arranged in discrete bundles were rapidly growing through the longitudinal axis of tectum and at stage 33 reached its posterior end. Cross sections of these fiber bundles at different positions revealed myelin ensheatment to be initiated at the end of stage 34 at the anterior pole of the tectum. Since in the optic nerve of the trout the onset of myelination occurred even earlier (stage 33), it is assumed that this differentiation process follows a rostro-caudal gradient during development of the optic pathway.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00206341
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 34
    Electronic Resource
    Electronic Resource
    Structure of the tail fin in teleosts (1983)
    Springer
    Cell & tissue research 230 (1983), S. 127-137 
    Details
    ISSN: 1432-0878
    Keywords: Tail fin ; Teleosts ; Actinotrichia ; Lepidotrichia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A morphologic study of the structure of the tail fin in eight species of teleosts was performed by aid of the Picrosirius-polarization method, which is a specific histochemical method for the detection of collagen in tissue sections. This structure is composed mainly of skeletal elements, the fin rays, covered by skin. Fin rays are bound to each other and to the surrounding tissues by a series of collagenous ligaments forming a complex, highly pliable and resistant structure. Although the general structural pattern of tail fins was consistent in all species studied, the comparative aspects reported in this paper show that variations in the form and size of their components are responsible for the morphologic diversities which are closely related to specific functional adaptations. Morphometric data on the number and size of actinotrichia in normal adult specimens are presented.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00216033
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 35
    Electronic Resource
    Electronic Resource
    Glomerular ultrastructure of the trout, Salmo gairdneri (1983)
    Springer
    Cell & tissue research 230 (1983), S. 205-218 
    Details
    ISSN: 1432-0878
    Keywords: Kidney ; Glomerulus ; Ultrastructure ; Teleosts ; Seawater adaptation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The epithelial ultrastructure of the glomerulus of fresh- and sea-water adapted rainbow trout, Salmo gairdneri was examined by scanning and transmission electron microscopy after in vivo-perfusion fixation. Adaptation to seawater for a period of up to 9 weeks was not associated with a change in glomerular size, although after one year in seawater both glomeruli and their capsules were significantly smaller than the glomeruli of freshwater adapted fish. In freshwater adapted trout the epithelial ultrastructure conformed to the general vertebrate pattern, with rounded podocytes, well-defined primary processes and interdigitating pedicels. Adaptation to seawater was associated with a marked increase in the frequency of cytoplasmic microprojections. In many glomeruli there was a flattening of the podocytes, broadening of the primary processes, and areas of closely-packed pedicels were common. These observations are discussed in the light of previous studies on the mammalian kidney and the changes of single nephron function known to be associated with adaptation of trout to increased environmental salinities.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00216040
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 36
    Electronic Resource
    Electronic Resource
    Effects of oestradiol-17β and testosterone on the histology of pituitary, liver, ovary and skin of previtellogenic Epinephelus akaara (Teleostei, Serranidae) (1983)
    Springer
    Cell & tissue research 231 (1983), S. 579-592 
    Details
    ISSN: 1432-0878
    Keywords: Steroids ; Vitellogenesis ; Oogenesis ; Histology ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The pituitary gland of the red grouper, Epinephelus akaara, was studied by histochemical techniques, and the prolactin cells, corticotrops, somatotrops, gonadotrops, thyrotrops, pars intermedia cells and neurohypophyseal cells, were identified. Oestradiol-17β treatment caused PAS-positive cells in the proximal pars distalis, presumably a mixture of gonadotrops and thyrotrops, to undergo hypertrophy, vacuolation and degranulation of cytoplasmic glycoprotein granules. Disappearance of cytoplasmic granules was also evident in the PAS-positive pars intermedia cells. Oestrogen-treated fish also showed an increase in the hepatosomatic index, and hepatocytes enlarged in size, their nuclear diameter increased and large vacuoles were formed in the cytoplasm. These changes in the liver were paralleled by a secretion of vitellogenin into the serum and an increased production of mucus by the thickened skin epithelium. Testosterone injections did not affect such changes, neither in the pituitary nor liver cells, but a proliferation of skin epithelial cells was noted. Neither oestradiol-17β nor testosterone stimulated ovarian incorporation of vitellogenin, but treatment with high doses (5 mg/kg) of oestradiol-17β or testosterone brought about a slight increase in the gonadosomatic index and atresia of some of the primary oocytes. The oogonial population size decreased in response to treatment with high doses of oestradiol-17β.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00218116
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 37
    Electronic Resource
    Electronic Resource
    Specific effect of calcium ions on the calcium-sensitive cells of the pars intermedia in the goldfish (1981)
    Springer
    Cell & tissue research 214 (1981), S. 23-31 
    Details
    ISSN: 1432-0878
    Keywords: Pituitary ; Pars intermedia ; Calcium ; Deionized water ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Cytological changes in the calcium-sensitive (Ca-s) cells (formerly termed PAS-positive cells) of the pars intermedia were investigated in the goldfish after adaptation to deionized water (DW), with or without addition of sodium, potassium and magnesium. These ions were added as chloride salts at concentrations similar to those present in fresh water (FW). The marked stimulation of the Ca-s cells is not inhibited in DW supplemented with Na+ (0.35 mM/1), K+ (0.05 mM/1), and Mg2+ (0.2mM/1) for a period of 24 days. The inhibition of the response to DW with calcium chloride (2 mM/1) is reproduced with calcium formiate (2 mM/1). These data show that chloride ions are not responsible for the regression of the Ca-s cells observed in goldfish kept in DW supplemented with calcium chloride. The effect of calcium ions on the Ca-s cells appears to be specific. These results support the hypothesis that the Ca-s cells synthesize a factor (hypercalcin?) involved in calcium regulation, and that its release is influenced by the calcium content of the environment. The role of the pars intermedia in calcium metabolism is strengthened by the present results. Biochemical data suggest the presence of a hypercalcemic factor in the pituitary of fish (Parsons et al. 1978) and are in agreement with the present cytological findings.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00235141
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 38
    Electronic Resource
    Electronic Resource
    Quantitative analysis of muscle breakdown during starvation in the marine flatfish Pleuronectes platessa (1981)
    Springer
    Cell & tissue research 214 (1981), S. 369-386 
    Details
    ISSN: 1432-0878
    Keywords: Muscle breakdown ; Ultrastructural changes ; Quantitative cytology ; Starvation ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The present study describes the effects of starvation for a duration of four months on the ultrastructure of skeletal muscles from the marine flatfish (Pleuronectes platessa L.). Starvation is associated with a decrease in resting metabolic rate from 20.1±2.2 to 11.6±1.5mg-O2/kg/h (P〈0.05) and muscle wasting. Median fibre size fell from 700 μm2 to 500 μm2 in intermediate (fast oxidative) and from 1,800 μm2 to 600 μm2 in starved, white (fast-glycolytic) muscle fibres. In contrast, median fibre size in red (slow oxidative) muscle remained within the range 300–400 μm2. The fraction of red fibre volume occupied by myofibrils (58.6%) and mitochondria (24.5%) did not change significantly with starvation. There was, however, a decrease in stored lipid (10.7% to 3.2%) and an alteration in the structure of the cristae in mitochondria from red muscle. Atrophy of white muscle fibres is associated with a decrease in both the diameter and fractional volume occupied by myofibrils (85.7% to 61.9% P 〈 0.01). In a high proportion of white fibres peripheral degeneration of Z-discs is evident causing an unravelling of the thin filament lattice. It is suggested that this allows a partial decrease in myofibril diameter and hence the maintenance of contractile function in muscle from starved fish. In severely degenerating white fibres, disorganised thick and thin filaments and numerous multimembrane lysosome-like vesicles are observed. Starvation results in an increase in the average content of mitochondria in white fibres from 2.2 to 6.7% (P〈0.01). In fed plaice mitochondria constitute less than 1% of the volume of the white fibre in 43.5% of the fibres. The proportion of white fibres containing more than 6% mitochondria increases from 6.5% to 58% with starvation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00249218
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 39
    Electronic Resource
    Electronic Resource
    Calcium-sensitive cells of the pars intermedia and osmotic balance in the eel (1982)
    Springer
    Cell & tissue research 222 (1982), S. 231-241 
    Details
    ISSN: 1432-0878
    Keywords: Pituitary ; Intermediate lobe ; Calcium-sensitive (PAS-positive) cells ; Teleosts ; Osmoregulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The structure of the PAS-positive calcium-sensitive (Ca-s) cells of the pars intermedia was investigated in eels kept in deionized water (DW) or fresh water (FW) supplemented with Ca2+ or Mg2+. Ca2+ (2mM) reduces considerably the response to DW; plasma osmolarity, Na+ and Ca2+ levels are not significantly affected. In eels adapted to DW for 21 or 28 days, showing highly stimulated Ca-s cells, an addition of CaCl2 for 2 days inhibits the release of granules, but does not immediately block their synthesis and the mitotic activity. The nuclear area is reduced, osmolarity and plasma sodium increase, but the rise in calcium is not always significant. Magnesium, at a 10-fold greater concentration than in FW (2 mM), slightly inhibits the release of secretory granules without reducing other indicators of stimulation. In Ca-enriched FW, the Ca-s cells appear inactive. These data show that the PAS-positive cells in the pars intermedia of the eel are calcium-sensitive, similar to those of the goldfish; their role in calcium regulation is briefly discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00213209
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 40
    Electronic Resource
    Electronic Resource
    Centrifugal innervation of the retina by luteinizing hormone releasing hormone (LHRH)-immunoreactive telencephalic neurons in teleostean fishes (1982)
    Springer
    Cell & tissue research 222 (1982), S. 313-323 
    Details
    ISSN: 1432-0878
    Keywords: Retina ; Telencephalic innervation ; Nucleus olfactoretinalis ; Teleosts ; LHRH immunohistochemistry ; HRP transport
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In cichlid, poecilid and centrarchid fishes luteinizing hormone releasing hormone (LHRH)-immunoreactive neurons are found in a cell group (nucleus olfactoretinalis) located at the transition between the ventral telencephalon and olfactory bulb. Processes of these neurons project to the contralateral retina, traveling along the border between the internal plexiform and internal nuclear layer, and probably terminating on amacrine or bipolar cells. Horseradish peroxidase (HRP) injected into the eye or optic nerve is transported retrogradely in the optic nerve to the contralateral nucleus olfactoretinalis where neuronal perikarya are labeled. Labeled processes leave this nucleus in a rostral direction and terminate in the olfactory bulb. The nucleus olfactoretinalis is present only in fishes, such as cichlids, poecilids and centrarchids, in which the olfactory bulbs border directly the telencephalic hemispheres. In cyprinid, silurid and notopterid fishes, in which the olfactory bulbs lie beneath the olfactory epithelium and are connected to the telencephalon via olfactory stalks, the nucleus olfactoretinalis or a comparable arrangement of LHRH-immunoreactive neurons is lacking. After retrograde transport of HRP in the optic nerve of these fishes no labeling of neurons in the telencephalon occurred. It is proposed that the nucleus olfactoretinalis anatomically and functionally interconnects and integrates parts of the olfactory and optic systems.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00213215
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 41
    Electronic Resource
    Electronic Resource
    Capillarisation, oxygen diffusion distances and mitochondrial content of carp muscles following acclimation to summer and winter temperatures (1982)
    Springer
    Cell & tissue research 222 (1982), S. 325-337 
    Details
    ISSN: 1432-0878
    Keywords: Temperature acclimation ; Quantitative cytology ; Capillarisation ; Skeletal muscle ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Many species of fish show a partial or complete thermal compensation of metabolic rate on acclimation from summer to winter temperatures. In the present study Crucian carp (Carassius carassius L.) were acclimated for two months to either 2° C or 28° C and the effects of temperature acclimation on mitochondrial content and capillary supply to myotomal muscles determined. Mitochondria occupy 31.4% and 14.7% of slow fibre volume in 2°C- and 28° C-acclimated fish, respectively. Fast muscles of coldbut not warm-acclimated fish show a marked heterogeneity in mitochondrial volume. For example, only 5 % of fast fibres in 28° C-acclimated fish contain 5 % mitochondria compared to 34 % in 2° C-acclimated fish. The mean mitochondrial volume in fast fibres is 6.1 % and 1.6 % for coldand warm-acclimated fish, respectively. Increases in the mitochondrial compartment with cold acclimation were accompanied by an increase in the capillary supply to both fast (1.4 to 2.9 capillaries/fibre) and slow (2.2 to 4.8 capillaries/fibre) muscles. The percentage of slow fibre surface vascularised is 13.6 in 28° C-acclimated fish and 32.1 in 2° C-acclimated fish. Corresponding values for fast muscle are 2.3 and 6.6 % for warm and cold-acclimated fish, respectively. Maximum hypothetical diffusion distances are reduced by approximately 23–30 % in the muscles of 2° C-compared to 28° C-acclimated fish. However, the capillary surface supplying 1 μ3 of mitochondria is similar at both temperatures. Factors regulating thermal compensation of aerobic metabolism and the plasticity of fish muscle to environmental change are briefly discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00213216
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 42
    Electronic Resource
    Electronic Resource
    VIP-, substance P-, gastrin/CCK-, bombesin-, somatostatin- and glucagon-like immunoreactivities in the gut of the rainbow trout, Salmo gairdneri (1982)
    Springer
    Cell & tissue research 223 (1982), S. 141-153 
    Details
    ISSN: 1432-0878
    Keywords: Neuropeptides ; Gut hormones ; Immunohistochemistry ; Radioimmunoassay ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The presence of peptides in the gastrointestinal tract of the rainbow trout, Salmo gairdneri, was investigated immunocytochemically. VIP-like immunoreactivity was demonstrated in nerves in all layers of the stomach and the intestine, whereas substance P-like immunoreactivity was localized to endocrine cells, predominantly in the mucosa of the stomach, and to nerves mainly concentrated in the myenteric plexus throughout the gut. Endocrine cells reactive to gastrin/CCK antiserum were demonstrated in the intestinal mucosa, while no immunoreactivity was found in the stomach. Bombesin-immunoreactive and somatostatin-immunoreactive cells were localized in the stomach mucosa, and cells reactive to glucagon antiserum in the intestinal mucosa. Radioimmunoassay of stomach mucosa and muscle confirmed the presence of VIP-like and substance P-like immunoreactivity in these tissues, while gastrin/CCK-like immunoreactivity was low and bombesin-like immuno-reactivity was insignificant. In conclusion, molecules resembling the mammalian brain-gut peptides may be involved in the neuronal and hormonal control of gut function in fish.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00221505
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 43
    Electronic Resource
    Electronic Resource
    Retrograde axon reaction following section of asynaptic nerve fibers (1982)
    Springer
    Cell & tissue research 223 (1982), S. 487-492 
    Details
    ISSN: 1432-0878
    Keywords: Axon reaction ; Chromatolysis ; Spinal cord ; Axotomy ; Neurofilaments ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The asynaptic spinal neurons of the gymnotid teleost Sternarchus albifrons show several distinct characteristics of the retrograde reaction of the perikaryon (which corresponds to chromatolysis in mammals) following axotomy. Nuclei of affected cells are characteristically eccentric. Large bundles of neurofilaments, never seen in normal perikarya of these cells, become prominent following axotomy. There is a marked increase in the number and size of dense bodies in the affected perikarya. Large arrays of parallel rough endoplasmic reticulum, never seen in normal cells, are frequent in the axotomized neurons. These results demonstrate that disconnection from synaptic terminals is not a necessary condition for the retrograde reaction of the perikaryon following axotomy.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00218470
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 44
    Electronic Resource
    Electronic Resource
    Relationships between the tubular system in the globules of the coronet cells of the saccus vasculosus and the cerebrospinal fluid in Gasterosteus aculeatus form leiurus (Teleostei) (1982)
    Springer
    Cell & tissue research 224 (1982), S. 105-115 
    Details
    ISSN: 1432-0878
    Keywords: Coronet cells ; Saccus vasculosus ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In the stickleback, Gasterosteus aculeatus, the globules of the coronet cells in the saccus vasculosus contain a tubular system that most probably communicates permanently with the lumen of the saccus. Only very few openings were found in random ultrathin sections. Injecting peroxidase into the cerebrospinal fluid revealed the communication between this tubular system and the cerebrospinal fluid. As early as 1 h after peroxidase injection the tracer was detected in the tubular system. This system increases the potential exchange surface between the coronet cells and the content of the saccular lumen, and may also facilitate the access of components of the cerebrospinal fluid (CSF), even of high molecular weight, into the globules. It remains to be determined whether the intratubular condensations (granules) are, as often believed, of secretory origin or are formed by accumulation of components of the CSF.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00217270
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 45
    Electronic Resource
    Electronic Resource
    Effects of steroids on gonadotropic (GTH) cells in the pituitary of rainbow trout, Salmo gairdneri, shortly after hatching (1982)
    Springer
    Cell & tissue research 224 (1982), S. 361-368 
    Details
    ISSN: 1432-0878
    Keywords: Steroids ; Pituitary ; Gonadotrops ; Immunocytochemistry ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Immunocytochemical reactions with anti-h(uman) TSHβ and anti-c(arp) GTHβ indicate that in juvenile rainbow trout, the dorsal basophils of the proximal pars distalis (ppd) are TSH cells, and that the ventral ones are GTH cells. Small GTH cells first appear in some fish at D(ay) 50 following fertilization (= D17 from hatching), when gonads are still undifferentiated. GTH cells increase greatly in number and size after D100. Contrary to treatment with 11β(OH)androstenedione, addition of methyl testosterone, progesterone and 17α(OH)progesterone stimulate the development of granular GTH cells in rainbow trout, shortly after hatching. It is suggested that steroid receptors in the brain or pituitary discriminate between 11-steroids and other steroids rather than between aromatizable androgens and other steroids.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00216879
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 46
    Electronic Resource
    Electronic Resource
    Apical surface of the epithelial cells in the gallbladder of the rainbow trout and the tench (1982)
    Springer
    Cell & tissue research 224 (1982), S. 449-454 
    Details
    ISSN: 1432-0878
    Keywords: Gallbladder epithelium ; Brush border ; Apocrine secretion ; Ultrastructure ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The free surface of the epithelial cells in the gallbladder of the rainbow trout (a predatory fish) and the tench (an omnivorous fish) is characterized by well-developed microvilli. They are irregularly arranged in the tench, but form a true brush border consisting of regularly aligned microvilli in the rainbow trout. In both species membrane-bounded cytoplasmic protrusions, up to 5 μm in diameter, extend from the apical surface. These protrusions are free of granules, secretory vesicles or other organelles; only in the tench some of them contain glycogen. Thus, the previously used terms “apocrine and droplet secretion” are not justified; the epithelial protrusions are now to be regarded as droplets of degenerated cytoplasm. Since they resemble the protrusions reported in fetal and postnatal epithelial cells in the gallbladder of higher vertebrates, interspecific differences are discussed. There is no significant correlation between the seasonal activity of the fish and the abundance or structure of the cytoplasmic protrusions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00216886
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 47
    Electronic Resource
    Electronic Resource
    Response of calcium-sensitive cells in the pars intermedia of the goldfish adapted to diluted sea water with different calcium and magnesium contents (1982)
    Springer
    Cell & tissue research 225 (1982), S. 497-505 
    Details
    ISSN: 1432-0878
    Keywords: Pituitary ; Intermediate lobe ; Calcium-sensitive (PAS-positive) cells ; Teleosts ; Osmoregulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Goldfish kept in diluted Ca-free sea water (SW) (23 or 30 %) or in Ca-Mg-deficient SW (23 %) have a limited survival, release large amounts of mucus, and show spasmodic seizures. Plasma calcium decreases. The PAS-positive calcium-sensitive (Ca-s) cells of the pars intermedia show a low activity in diluted SW and in 23 % Mg-free SW. In diluted Ca-free SW, Ca-s cells are stimulated, but cell hypertrophy is not uniform and often restricted to an area adjacent to the proximal pars distalis. Nuclear hypertrophy is significant in the reactive area, although less pronounced or even absent at the periphery of the lobe. Mitotic activity occurs in the Ca-s cells of goldfish gradually adapted to diluted Ca-free SW and Ca-Mg-deficient SW, and sacrificed after 19 and 28 days, respectively. A general stimulation of the Ca-s cells, which remains less intense than that in goldfish kept in deionized water (DW), appears unable to ensure the survival of the goldfish in an isosmotic Ca-free environment containing Mg2+ (0.1, 12 or 16.8 mM). These data are compared with those obtained in the eel kept in Ca-free SW.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00214800
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 48
    Electronic Resource
    Electronic Resource
    Extravascular circulation in the pituitary of Mugil cephalus (Teleostei) (1982)
    Springer
    Cell & tissue research 225 (1982), S. 567-579 
    Details
    ISSN: 1432-0878
    Keywords: Extravascular circulation ; Pituitary ; Teleosts ; Horseradish ; peroxidase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Extravascular circulation in the pituitary of Mugil cephalus was investigated by injecting live fish with horseradish peroxidase and studying the distribution of the enzyme in the gland. The principal components of the extravascular circulatory system are the pericapillary spaces, and, arising from them, the interlobular and circumhypophyseal spaces. Extensions of these spaces penetrate the glandular parenchyma of the pars distalis, where they merge with pericellular spaces. In the neurohypophysis, pericapillary spaces are connected to the periaxonal spaces. Capillaries penetrating from the proximal neurohypophysis into the pars distalis are accompanied by neurosecretory axons. These axons form a mass of tissue which is limited near the capillaries by the pericapillary spaces and near the adenohypophysis by the interlobular spaces. Toward the interior of the adenohypophysis the amount of nervous tissue accompanying the capillaries progressively diminishes, thus reducing the distance between pericapillary and interlobular spaces. Within the pars distalis, the neurosecretory axons accompanying the capillaries are sparse, and the secretory and stellate cells are mostly located directly adjacent to the pericapillary spaces. In the neuro-intermediate lobe, interlobular spaces outline the neuro-adenohypophyseal boundary. The relationship between extravascular spaces and hormone-secreting cells varies in the different regions of the adenohypophysis depending upon the type of neurosecretory innervation in the respective region. In the regions of prolactin and gonadotropin cells, where neurosecretory axons are in direct contact with the secretory cells, the hormone-secreting and stellate cells are adjacent to the pericapillary spaces. In the regions of ACTH and STH cells, secretory and stellate cells are found adjacent to the interlobular spaces, which are interposed between the cells and the neurosecretory axons.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00214805
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 49
    Electronic Resource
    Electronic Resource
    LHRH-immunoreactive cells in the brain of the three-spined stickleback, Gasterosteus aculeatus L. (Gasterosteidae) (1982)
    Springer
    Cell & tissue research 226 (1982), S. 695-699 
    Details
    ISSN: 1432-0878
    Keywords: LH-FSH releasing hormone ; Hypothalamus ; Thalamus ; Tegmentum mesencephali ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Cells immunoreactive with an anti-LHRH serum were visualized in the brain of the three-spined stickleback, Gasterosteus aculeatus, by means of the PAP technique. Positive cells were found in a periventricular position in the nucleus praeopticus pars magnocellularis, the nucleus dorsomedialis thalami, the nucleus ventromedialis thalami, the nucleus periventricularis posterior, and in the periventricular dorsomedian tegmentum. These cells were frequently observed to contact the CSF.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00214796
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 50
    Electronic Resource
    Electronic Resource
    Ontogeny of the photoreceptors in the embryonic retina of the viviparous guppy, Poecilia reticulata P. (Teleostei) (1983)
    Springer
    Cell & tissue research 230 (1983), S. 469-486 
    Details
    ISSN: 1432-0878
    Keywords: Ontogeny ; Photoreceptors ; Retina ; Ultrastructure ; Teleosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Ultrastructural analyses of retinal development in the guppy embryo show that at midgestation all types of photoreceptors are differntiated in the fundus, and at birth differentiation extends over the whole retina. Formation of discs of outer segments is more rapid in rods than in cones. Double cones differentiate simultaneously with long single cones and are formed by the adhesion of two primordial inner segments; short single cones develop last. Wherever cones are differentiated, they are arranged in an adult-type square mosaic. The rods in the embryo, as opposed to the adult, are likewise regularly arranged within the mosaic unit. These results are at variance with the generally held opinion that adult teleosts which possess duplex retinae have larvae with pure cone retinae, and that rods, double cones and mosaics appear in late larval life or only at metamorphosis. In the double cones of the guppy embryo subsurface cisternae develop along the adjoining primordial inner segments. Additionally, regularly distributed subsurface cisternae are formed in the regions of intimate contact of long single cones with double cones and rods. We suggest that the early development of rods and double cones, and a square-mosaic with regular distribution of rods and subsurface cisternae, provide the newly born with a fully functional optical apparatus, especially suited to perception of movements. This is necessary for its survival against predatory, especially maternal, attacks.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00216193
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 51
    Electronic Resource
    Electronic Resource
    Immunocytochemical identification of thyrotropin (TSH)-producing cells in pituitary glands of several species of teleosts with antiserum to human TSH β subunit (1983)
    Springer
    Cell & tissue research 231 (1983), S. 199-204 
    Details
    ISSN: 1432-0878
    Keywords: Immunocytochemistry ; Human TSH β subunit ; Teleosts ; TSH cells
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A rabbit antiserum raised against human thyrotropin (TSH) β subunit (anti-human β-TSH) was used to identify TSH cells in the pituitaries of five species of teleosts by means of the unlabeled antibody peroxidase-antiperoxidase (PAP) technique. The anti-human β-TSH reacted only with polygonal basophils located in the rostral pars distalis (RPD) in the pituitaries of sexually immature eel (Anguilla japonica). In the pituitaries of medaka (Oryzias latipes) and white-edged rockfish (Sebastes taczanowskii), this serum reacted specifically with only one cell-type located in the antero-dorsal proximal pars distalis (PPD) and antero-ventral PPD, respectively. In the pituitaries of two species of salmonids, sexually immature rainbow trout (Salmo gairdneri) and sexually mature chum salmon (Oncorhynchus keta), the anti-human β-TSH bound to the polygonal basophils in the ventral PPD adjacent to the RPD. Thus, the present immunocytochemical study identified polygonal basophils located in the RPD or PPD as TSH cells in five species of teleosts.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00215786
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...