Summary
Male rats were divided in two experimental groups. In group I two partes distales of the hypophysis were grafted under the kidney capsule and in group II two complete hypophyses were transplanted. Animals were killed 5 to 22 months after the operation. The grafted tissue was excised and processed for light and electron microscopy.
The transplanted pars distalis tissue showed a well developed vascularisation in contrast to the pars intermedia which appeared poorly vascularised. Six different cell types were observed in grafted pars distalis. They correspond to the different types of cells found in the rat pars distalis “in situ”. The predominant cell type in the graft displayed all the morphological characteristics of stimulated prolactotrophs. Pars intermedia cells appeared hypertrophied resembling the MSH cells under stimulation. Two types of syncytial formations were frequently seen. One of them appeared to originate from prolactotrophs and the other from MSH cells. Bodian impregnated fibres and structures resembling either growth cones of axons or typical nerve endings were observed in the pars intermedia of long-term grafted hypophyses. Pituicytes remained as isolated clusters of cells. Canaliculi lined by two or more pituicytes were observed. Saccular formations resembling the hypophyseal cleft appeared in all grafts studied. The present findings suggest that in the male rat the chronically grafted pituitary gland is capable of synthesising most or all the hormones which are known to be produced by the gland “in situ”. Furthermore, prolactin and MSH seem to be the predominant secretion of the transplanted pituitary.
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References
Aguado, L.I., Benelbaz, G.A., Gutierrez, L., Rodríguez, E.M.: Ultrastructure of the rat pineal gland grafted under the kidney capsule. Cell Tiss. Res. (in press) (1976)
Beddow, D.G., McCann, S.N.: Effect of median eminence lesions on the function of multiple pituitary homografts with particular reference to the secretion of gonadotrophins and growth hormone. Endocrinology 84, 595–605 (1969)
Boddingius, J.: An argyrophil fibrillar system and amitotic nuclear division in pars intermedia cells of the rainbow trout (Salmo irideus). Z. Zellforsch. 108, 59–80 (1970)
Del Cerro, M.P., Snider, R.S.: Studies on the developing cerebellum. Ultrastructure of the growth cones. J. comp. Neurol. 133, 341–361 (1968)
Everett, J.W.: Functional corpora lutea maintained for months by autografts of rat hypophysis. Endocrinology 58, 786–796 (1956)
Farquhar, M.: Processing of secretory products by cells of the anterior pituitary gland. In: Subcellular organization and function in endocrine tissues, pp. 79–124. Eds.: H. Heller and K. Lederis. Cambridge: Cambridge University Press 1971
Feltkamp, C.A.: Changes in cellular composition of hypophyseal isografts in mice. III European Conference on Electron Microscopy, pp. 483–484. Prague, Czechoslovakia: Publishing House of the Czechoslovak Academy of Sciences 1964
Foster, C.L.: Relationships between ultrastructure and function in the adenohypophysis of the rabbit. In: Subcellular organization and function in endocrine tissues. Eds.: H. Heller and K. Lederis, pp. 125–146. Cambridge: Cambridge University Press 1971
Heap, P.F., Lederis, K., Neumann, F.: Effects of cyproterone on the ultrastructure of the rat adenohypophysis. In: Subcellular organization and function in endocrine tissues, pp. 147–160. Eds. H. Heller and K. Lederis. Cambridge: Cambridge University Press 1971
Hymer, W.C., McShan, W.H., Cristiansen, R.G.: Electron microscopic studies of anterior pituitary glands from lactating and estrogen-treated rats. Endocrinology 69, 81–90 (1961)
Ishikawa, H., Soyama, F., Yoshimura, F.: ACTH secretion from the pituitary transplanted in apposition with the adrenal cortex under the renal capsule. Endocr. jap. 16, 331–349 (1969)
Kurosumi, K., Oota, Y.: Electron microscopy of two types of gonadotrophs in the anterior pituitary glands of persistent estrous and diestrous rats. Z. Zellforsch. 85, 34–46 (1968)
Masur, S.K.: Fine structure of the autotransplanted pituitary in the red eft, Notophthalmus viridescens. Gen. comp. Endocr. 12, 12–32 (1969)
Masur, S.K., Holtzman, E., Kashner, L.: An electron microscopic and cytochemical study of the transplanted newt pituitary gland. J. Cell Biol. 39, 86 A (1968)
McShan, W.H.: Secretory granules from anterior pituitary glands. In: Subcellular organization and function in endocrine tissues, pp. 161–184. Eds.: H. Heller and K. Lederis. Cambridge: Cambridge University Press 1971
Meites, J., Nicoll, C.S.: Adenohypophysis: prolactin. Ann. Rev. Physiol. 28, 57–88 (1966)
Nakane, P.K.: Classifications of anterior pituitary cell types with immunoenzyme histochemistry. J. Histochem. Cytochem. 18, 9–20 (1970)
Nemeskéry, A., Németh, A., Sétáló, Gy., Vigh, S., Halász, B.: Cell differentiation of the fetal rat anterior pituitary in vitro. Cell Tiss. Res. 170, 263–273 (1976)
Nikitovich-Winer, M.B., Everett, J.W.: Histological changes in grafts of rat pituitary on the kidney and upon re-transplantation under the diencephalon. Endocrinology 65, 357–368 (1959)
Rennels, E.G.: An electron microscope study of pituitary autograft cells in the rat. Endocrinology 71, 713–722 (1963)
Rodriguez, E.M.: Fixation of the central nervous system by perfusion of the cerebral ventricles with a threefold aldehyde mixture. Brain Res. 15, 395–412 (1969)
Rodríguez, E.M., Dellmann, H.D.: Hormonal content and ultrastructure of the disconnected neural lobe of the grass frog (Rana pipiens). Gen. comp. Endocr. 15, 272–288 (1970)
Romeis, B.: Der Drüsenteil der Hypophyse. In: Innersekretorische Drüsen II Hypophyse, pp. 64–239. Handbuch der mikroskopischen Anatomie des Menschen. Ed.: W. v. Möllendorff. Berlin: Springer 1940
Sanders, A.E., Rennels, E.G.: Evidence on the cellular source of luteotrophin derived from a study of rat pituitary autografts. Z. Zellforsch. 49, 263–274 (1959)
Van Dongèn, W.J., Jørgensen, C.B., Larsen, L.O., Rosenkilde, P., Lofts, B., Van Oordt, P.G.W.J.: Function and cytology of the normal and autotransplanted pars distalis of the hypophysis in the toad, Bufo bufo (L). Gen. comp. Endocr. 6, 491–518 (1966)
Venable, J., Coggeshall, R.: A simplified lead citrate stain for use in electron microscopy. J. Cell Biol. 25, 407–408 (1965)
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Supported by the National Research Council of Argentina. Grant 7315/74
Members of the Research Career of Conicet, Argentina
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Santolaya, R.C., Rodríguez, E.M. Ultrastructure of the male rat hypophysis chronically grafted under the kidney capsule. Cell Tissue Res. 179, 271–284 (1977). https://doi.org/10.1007/BF00219801
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DOI: https://doi.org/10.1007/BF00219801