Gonadotropic cells in the pituitary of teleosts
van Oordt, P.G.W.J. (1982). Gonadotropic cells in the pituitary of teleosts, in: Richter, C.J.J. et al. (Ed.) Proceedings of the International Symposium on of Fish, Wageningen, The Netherlands 2-6 August 1982. pp. 44-48 In: Richter, C.J.J.; Goos, H.J.Th. (Ed.) (1982). Proceedings of the International Symposium on reproductive physiology of fish, Wageningen, The Netherlands 2-6 August 1982. International Symposium on the Reproductive Physiology of Fish. Centre for Agricultural Publishing and Documentation: Wageningen. ISBN 90-220-0818-5. X, 256 pp., more In: International Symposium on the Reproductive Physiology of Fish. Museo Nacional de Ciencias Naturales. , more |
| Abstract | Immunocytochemical and histophysiological evidence points to globular basophils as the source of a glycoprotein gonadotropic hormone (GTH). This cell type may be situated in various parts of the adenohypophysis, but in many species is concentrated in the ventral region of the proximal pars distalis(PPD). It has irregular cisternae of the granular endoplasmic reticulum (GER), secretory granules of varying electron density, 200-500 nm in diameter, and larger, less electron dense globules. Among the contents of granules and globules are material reacting with anti-(bèta)-teleost-GTH, and acid phosphatase. Extrusion of GTH is accompanied by a loss of granules and globules and an increase in number and size of the GER cisternal. Cisternal cells and a variety of other cell types have been described as a separate type of gonadotrop. However, it seems that even if two morphological types of gonadotrops can be distinguished, both may be able to produce maturational as well as vitellogenic GTH. The physiological significance of secretory globules apart from granules is unknown. The production and extrusion of GTH is regulated by peripheral and central factors. Among the central stimuli are various types of neurosecretory fibres that in many teleosts penetrate the adenohypophysis and directly innervate glandular cells, including gonadotrops. |
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