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  • 1
    Electronic Resource
    Electronic Resource
    Cytophysiology and innervation of gonadotropic cells in the pituitary of the Black Molly (Poecilia latipinna) (1976)
    Springer
    Cell & tissue research 174 (1976), S. 35-54 
    Details
    ISSN: 1432-0878
    Keywords: Pituitary ; Teleost ; GTH-cells ; Innervation ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In the male black molly, Poecilia latipinna, morphological and functional aspects of the gonadotropic (GTH-)cells have been studied at the ultrastructural level. The cells exclusively occupy the ventral and lateral areas of the meso-adenohypophysis. In the black molly there is evidence of the presence of only one type of gonadotropic cell. In the GTH-cells of most specimens, the rough endoplasmic reticulum is weakly developed. The secretory vesicles are characterized by cores with varying diameters; this variation was not observed in the secretory vesicles of the other types of pituitary cells, except in the TSH-cells. After applying a histochemical method for the demonstration of polysaccharides, small black deposits appear in the core of the secretory vesicles of the GTH and TSH-cells only; this indicates the glycoproteinaceous nature of the hormones produced in these cells. Male black mollies treated with methyl-testosterone have significantly smaller GTH-cells and a lesser number of secretory vesicles and mitochondria in these cells. GTH-cell activity in Poeciliinae may be thus influenced by androgens by means of a negative feed-back mechanism. The GTH-cells are innervated by both type A and type B neurosecretory fibres. There are indications that the type A fibres may originate from the pars lateralis cells of the nucleus lateralis tuberis; the origin of the type B fibres is uncertain.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00222149
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    Paper (German National Licenses)
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  • 2
    Electronic Resource
    Electronic Resource
    The gonadotropic cells in the pituitary of the black molly, Mollienisia latipinna, and other teleosts, identified by the immunofluorescence technique in normal and androgen-treated animals (1976)
    Springer
    Cell & tissue research 167 (1976), S. 211-219 
    Details
    ISSN: 1432-0878
    Keywords: Teleosts ; Pituitary ; GTH ; Immunofluorescence
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Using anti-carp-gonadotropic-γ-globulin, the indirect immunofluorescence technique was applied to sections of the pituitary of 12 teleost species. From the investigated species, the Poeciliinae, and especially the black molly, showed a distinct localization of fluorescent cells in the mesoadenohypophysis. Strong fluorescence was observed in the ventralmost region, containing the presumed gonadotropic cells; weak fluorescence was observed in the dorsal region, in the presumed thyrotropic cells. The possibility of an unspecific reaction with TSH-cells in the latter region is discussed. Treatment of male black mollies for 38 days with methyltestosterone resulted in a loss of fluorescence in the ventral region of the meso-adenohypophysis, whereas there was no decrease of the fluorescence in the dorsal region. The results support the hypothesis that the ventral basophils in the mesoadenohypophysis produce gonadotropic hormone.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00224328
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    Paper (German National Licenses)
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  • 3
    Electronic Resource
    Electronic Resource
    Origin and destination of globules and irregular masses in the gonadotropin cells from the pituitary of the African catfish, Clarias gariepinus: a morphological study (1995)
    Springer
    Cell & tissue research 280 (1995), S. 113-122 
    Details
    ISSN: 1432-0878
    Keywords: Pituitary ; Gonadotrops ; Crinophagy ; Electron microscopy ; Enzyme cytochemistry ; Immunocytochemistry ; Autoradiography ; Catfish, Clarias gariepinus (Teleostei)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The possible function of globules and irregular membrane-bound masses in the gonadotropin cells of the pituitary of Clarias gariepinus was studied. Strong secretory stimulation led to the disappearance of the secretory granules from gonadotropin cells but globules and irregular masses remained present. Acid phosphatase was detected enzyme-cytochemically in both globules and irregular masses. Radiolabelling with tritiated amino acids followed by autoradiography demonstrated that globules received radioactive material after secretory granules. The latter received radioactive material within 75 min of administration of radioactive amino acids but globules and irregular masses did not. Although some globules became radioactively labelled within 24 h of the administration of radioactive amino acids, irregular masses remained unlabelled during this period. Secretory granules reacted positively with antisera against α and β gonadotropin subunits, whereas globules and irregular masses only reacted with the antiserum against the β subunit. A moderate anti-7B2 immunoreactivity was demonstrated in secretory granules and globules, whereas irregular masses labelled strongly. The combined cytological results indicate that globules and irregular masses are degradative, possibly crinophagic structures which develop by fusional events from secretory granules to globules and then to irregular masses.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00304516
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  • 4
    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
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    Paper (German National Licenses)
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