Summary
The adenohypophysis of Thamnophis is produced from the stomodeal epithelium in two steps: a diverticulum, enlarging by addition of epithelium to its basal end, defines the posterior end of the gland, and a subsequent infolding promoted by mesenchymal movements occurs in epithelium anterior to the original diverticulum and forms the anterior end of the anlage and the hypophyseal stalk. Immediately thereafter the pars intermedia (PI) is demarcated, first by a luminal, subsequently by an external constriction, and secretion granules are found in the gland. At this time granulated cells are rare in the PI, and in the pars distalis (PD) they are more frequent in the anterior end. Secretion granules occur in cells away from the surface of the residual lumen; the lumen is lined by presumptive stellate cells. The early appearance of secretion granules in cells of the embryonic pituitary, and the presence in the hypophyseal stalk of both mucussecreting cells and cells with granules similar to those of the PD suggest that some differentiation occurs in the stomodeal epithelial cells before the definitive pouch is formed.
The absence of lateral lobes in the embryonic hypophysis precludes the development of the pars tuberalis in Thamnophis.
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References
Baumgartner, E.A.: The development of the hypophysis in reptiles. J. Morph. 28, 209–285 (1916)
Cieslak, E.S.: Relations between the reproductive cycle and the pituitary gland in the snake Thamnophis radix. Physiol. Zool. 18, 299–329 (1945)
Clark, H.: Embryonic series in snakes. Science 85, 569–570 (1937)
De Beer, G.R.: The Comparative Anatomy, Histology, and Development of the Pituitary Body. London: Oliver and Boyd 1926
Dellmann, H., Stoeckel, M.E., Hindelang-Gertner, C., Porte, A., Stutinsky, F.: A comparative ultrastructural study of the pars tuberalis of various mammals, the chicken and the newt. Cell Tiss. Res. 148, 313–329 (1974)
Enemar, A.: The development of the hypophysial vascular system in the lizards Lacerta a. agilis Linnaeus and Anguis fragilis Linnaeus and in the snake Natrix n. natrix (Linnaeus), with comparative remarks on the Amniota. Acta Zool. (Stockholm) 41, 141–237 (1960)
Ferrand, R.: Étude expérimentale des facteurs de la différenciation cytologique de l'adénohypophyse chez l'embryon de poulet. Arch. Biol. 83, 297–371 (1972)
Ferray, L.: Le complexe diencéphalohypophysaire de la couleuvre a collier (Tropidonotus natrix). Ann. Embryol. Morph. 6, 169–178 (1973)
Gaupp, E.: Über die Anlage der Hypophyse bei Sauriern. Arch. f. mikr. Anat. 42, 569–580 (1893)
Glücksmann, A.: Cell deaths in normal vertebrate ontogeny. Biol. Rev. 26, 59–86 (1951)
Gray, P.: The Microtomist's Formulary and Guide. New York: Blakiston 1954
Haller, G.: Über die Entwicklung der Hypophyse bei Reptilien. Gegen. Morph. Jahr. 53, 305–318 (1923)
Herlant, M., Pasteels, J.J.: Etude comparée du développement de l'hypophyse chez deux Lacertiliens africains: Mabuia megalura (Peters) et Chamaeleo bitaeniatus Ellioti (Gunther). Arch. Biol. 66, 167–193 (1955)
Hoffmann, C.K.: Weitere Untersuchungen zur Entwicklungsgeschichte der Reptilien. Gegen. Morph. Jahr. 11, 176–219 (1886)
Holmes, R.L., Ball, J.N.: The Pituitary Gland, Cambridge: University Press 1974
Mercer, E.H.: A scheme for section staining in electron microscopy. J. Roy. Microsc. Soc. 81, 179–186 (1963)
Mertens, R., Wermuth, H.: Die Amphibien und Reptilien Europas. Frankfurt am Main: W. Kramer 1960
Mikami, S., Hashikawa, T., Farner, D.S.: Cytodifferentiation of the adenohypophysis of the domestic fowl. Z. Zellforsch. 138, 299–314 (1973)
Milcou, S.M., Ionesco, M.D., Cimpeanu, L., Petrovici, Al., Dancasiu, M.: Les types cellulaires de pars distalis de l'hypophyse chez Natrix natrix. Rev. Roum. Endocrinol. 8, 365–369 (1971)
Miller, M.: The histogenesis of the endocrine organs of the viviparous lizard, Xantusia vigilis, Gen. comp. Endocr. 3, 579–605 (1963)
Pearson, A.K., Licht, P.: Embryology and cytodifferentiation of the pituitary gland in the lizard Anolis carolinensis. J. Morph. 144, 85–118 (1974)
Rathke, H.: Entwickelungsgeschichte der Natter (Coluber natrix). Königsberg: Gebrüder Bornträger 1839
Saint Girons, H.: Particularités anatomiques et histologiques de l'hypophyse chez les Squamata. Arch. Biol. 72, 211–299 (1961a)
Saint Girons, H.: Evolution des differéntes catégories cellulaires de l'adénohypophyse, chez Vipera aspis (L.), au cours de la croissance. C.R. Seances Soc. Biol. 155, 1207–1211 (1961b)
Saint Girons, H.: The pituitary gland. In: Biology of the Reptilia (C. Gans, T.S. Parsons, eds.) Vol. 3, p. 135–199. New York, Academic Press 1970
Siler, K.A.: The cytological changes in the hypophysis cerebri of the garter snake (Thamnophis radix) following thyroidectomy. J. Morph. 59, 603–623 (1936)
Van Denburgh, J.: The Reptiles of Western North America. San Francisco: Cal. Acad. Sci. 1922
Wingstrand, K.: The Structure and Development of the Avian Pituitary. Lund: C. W. K. Gleerup 1951
Wingstrand, K.: Comparative anatomy and evolution of the hypophysis. In: The pituitary Gland (G.W. Harris, B. T. Donovan, eds.), Vol. 1, p. 58–126. Berkeley: University of California Press, 1966
Woerdeman, M.W.: Vergleichende Ontogenie der Hypophysis. Arch. f. mikr. Anat. 86, 198–291 (1914)
Wyeth, F.J., Row, R.W.H.: The structure and development of the pituitary body in Sphenodon punctatus. Acta Zool. (Stockholm). 4, 1–63 (1923)
Zehr, D.R.: Stages in the normal development of the common garter snake, Thamnophis sirtalis sirtalis. Copeia 1962, 322–329 (1962)
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Pearson, A.K., Wurst, G.Z. Embryonic differentiation of the pituitary in a snake (Thamnophis brachystoma). Anat Embryol 151, 141–155 (1977). https://doi.org/10.1007/BF00297477
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DOI: https://doi.org/10.1007/BF00297477