Summary
To see whether adenohypophysial tissue has the capacity of self-differentiation, Rathke's pouch together with part of the neurohypophysial primordium was isolated from 12-(Group A), 14- (Group B) and 15-day-old (Group C) rat fetuses and cultivated for 9, 6 and 5 days, respectively. Electron microscopic examination of these explants showed many adenohypophysial cells containing electron dense granules, indicative of cytodifferentiation in all groups. Three cell types were distinguishable on the basis of the size of their granules. Variable amounts of neurohypophysial tissue were seen in some explants of Groups B and C, but not A. This “pars nervosa” contained pituicytes with lipid-like inclusions in their cytoplasm but no neurosecretory axons. The adenohypophysial cells abutting on the pars nervosa were arranged rather regularly like cells of the pars intermedia which contained a few granules of about 200 mμ diameter.
From these data it is concluded that in rats granule formation in the adenohypophysial primordial cells starts in the absence of hypothalamic neurosecretory substances. It is uncertain from this study whether these cells actually contain hypophysial hormones.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Atwell, W. J.: Differentiation and function of heterotopic autoplastic transplants of the amphibian hypophysis. Proc. Soc. exp. Biol. (N.Y.)33, 224–226 (1935)
Atwell, W. J.: Functional transplants of the primordium of the epithelial hypophysis in Amphibia. Anat. Rec.68, 431–447 (1937)
Costoff, A., McShan, W. H.: Isolation and biological properties of secretory granules from rat anterior pituitary gland. J. Cell. Biol.43, 564–574 (1969)
Daikoku, S., Kinutani, M., Watanabe, Y. G.: Role of hypothalamus on development of adenohypophysis: An electron microscopic study. Neuroendocrinology11, 284–305 (1973)
Driscoll, W. T., Eakin, R. M.: The effects of sucrose on amphibian development with special reference to the pituitary body. J. exp. Zool.129, 149–176 (1955)
Etkin, W.: Embryonic determination of the adenohypophysis in the wood frog,R. sylvatica. Anat. Rec.131, 548 (1958a)
Etkin, W.: Independent differentiation in components of the pituitary complex in the wood frog. Proc. Soc. exp. Biol. (N.Y.)97, 388–393 (1958b)
Ferrand, R.: Différenciation en greffe chorio-allantoïdienne de l'épithelium de la poche de Rathke d'embryons de caille et de poulet. C. R. Soc. Biol. (Paris)163, 2669–2672 (1969)
Ferrand, R.: Étude expérimentale des facteurs de la différenciation cytologique de l'adénohypophyse chez l'embryon de poulet. Arch. Biol. (Liège)83, 297–371 (1972)
Ferrand, R., Le Douarin, N.: Différenciation de tissu adénohypophysaire à partir de la poche de Rathke prélevée après le stade de la détermination chez l'embryon de Poulet et mise au contact de divers mésenchymes. C. R. Soc. Biol. (Paris)162, 2215–2218 (1968)
Fink, G., Smith, G. C.: Ultrastructural features of the developing hypothalamo-hypophysial axis in the rat. A correlative study. Z. Zellforsch.119, 208–226 (1971)
Halász, B., Pupp, L., Uhlarik, S.: Hypophysiotrophic area in the hypothalamus. J. Endocr.25, 147–154 (1962)
Hanaoka, Y.: The effects of posterior hypothalectomy upon the growth and metamorphosis of the tadpole ofRana pipiens. Gen. comp. Endocr.8, 417–431 (1967)
Hatakeyama, S.: Electron microscopic study of the anencephalic adenohypophysis with reference to the adrenocorticotrophs and their correlation with the functional differentiation of the hypothalamus during the foetal life. Endocr. jap.16, 187–203 (1969)
Hyypä, M.: Differentiation of the hypothalamic nuclei during ontogenetic development in the rat. Z. Anat. Entwickl.-Gesch.129, 41–52 (1969)
Ishikawa, H.: Differentiation of the anterior pituitary cells by neurohormones (in Japanese). Zool. Mag. (Tokyo)79, 405–406 (1970)
Le Douarin, G., Ferrand, R.: Différenciation fonctionnelle de l'ébauche épithéliale de l'adénohypophyse isolée du plancher encéphalique: activité thyréotrope. C. R. Acad. Sci. (Paris)266, 697–699 (1968)
Le Douarin, N., Ferrand, R., Le Douarin, G.: La différenciation de l'ébauche épithéliale de l'hypophyse séparée du plancher encéphalique et placée dans des mésenchymes hétérologues. C. R. Acad. Sci. (Paris)264, 3027–3029 (1967)
Mollenhauer, H. H.: Plastic embedding mixtures for use in electron microscopy. Stain Technol.39, 111–114 (1964)
Moscona, H., Moscona, A.: The development in vitro of the anterior lobe of the embryonic chick pituitary. J. Anat. (Lond.)86, 278–286 (1952)
Nikitovitch-Winer, M., Everett, J. W.: Functional restitution of pituitary grafts re-transplanted from kidney to median eminence. Endocrinology63, 916–930 (1958)
Nikitovitch-Winer, M., Everett, J. W.: Histocytologic changes in grafts of rat pituitary on the kidney and upon re-transplantation under the diencephalon. Endocrinology65, 357–368 (1959)
Reynolds, E. S.: The use of lead citrate at high pH as an electron-opaque stain in electron microscopy. J. Cell. Biol.17, 208–212 (1963)
Salazar, H., MacAulay, M. A., Charles, D., Pardo, M.: The human hypophysis in anencephaly. I. Ultrastructure of the pars distalis. Arch. Path.87, 201–211 (1969)
Sobel, H.: The behaviour in vitro of dissociated embryonic pituitary tissue. J. Embryol. exp. Morph.6, 518–526 (1958)
Trowell, O. A.: The culture of mature organs in a synthetic medium. Exp. Cell. Res.16, 118–147 (1959)
Yoshimura, F., Harumiya, K., Kiyama, H.: Light and electron microsopic studies of the cytogenesis of anterior pituitary cells in perinatal rats in reference to the development of target organs. Arch. histol. jap.31, 333–369 (1970)
Author information
Authors and Affiliations
Additional information
We thank Mr I. Shimada for preparation of the micrographs.
Rights and permissions
About this article
Cite this article
Watanabe, Y.G., Matsumura, H. & Daikoku, S. Electron microscopic study of rat pituitary primordium in organ culture. Z.Zellforsch 146, 453–461 (1973). https://doi.org/10.1007/BF02347175
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF02347175