A Study of the Testis Tubules, Interstitial Tissue, and Sex Characters (Thumb-pads and Wolffian Ducts) of Normal and Hypophysectomized Frogs (Rana esculenta)

Abstract

ABSTRACT 1. After hypophysectomy in October the testes and some sex characters (Wolffian ducts and thumb-pads) of Rana esculenta were investigated during 9 subsequent months. 2. The so-called prespermatogenesis (Champy, 1913) is completed normally after hypophysectomy, but the primary spermatogonia lose their capacity for division. Therefore 8 months after the operation the testis tubules contain only primary spermatogonia. 3. The spermatogonia of the testes of control frogs, kept under laboratory conditions from October onwards, show a precocious activity during the winter, but in July new spermatozoa have not yet been formed. 4. In both control and experimental frogs the spermatozoa, formed during late summer and autumn, almost entirely disappear in the spring, even in the absence of copulations. 5. During the winter and spring months the interstitial testis cells of the control frogs undergo a reduction in both number and function, and this coincides with the increased activity in the testis tubules which occurs under laboratory conditions. 6. Conversely the decreased spermatogenetic activity, caused by hypophysectomy, coincides with an increase in the number of interstitial cells. The cytoplasm of these cells, however, is greatly reduced, although the nuclei maintain their typical form and size till at least 9 months following the operation. 7. Thumb-pads and Wolffian ducts are strongly affected by hypophysectomy. 8. The cytological changes brought about in the interstitial cells of R. esculenta after hypophysectomy do not quite coincide with changes in the development of the thumb-pads and Wolffian ducts. Therefore no new evidence for the endocrine function of these cells can be given.