HORMONE SENSITIVITY OF GERM-CELLS IN STAGE-XIV AND IN STAGE-I OF THE RAT SPERMATOGENIC CYCLE

Previous data have been inconclusive with respect to whether the meiot ic degenerations that occur in stage XIV of the spermatogenic cycle ar e increased after hypophysectomy. Meiotic cell degenerations in Stage XIV and early Stage I of the spermatogenic cycle were enumerated to de termine if the advanced generation of meiotic cells were influenced by hormonal deprivation subsequent to hypophysectomy and, if so, could c ellular degenerations be prevented by supplementation with either test osterone or recombinant FSH during the period of hypophysectomy. The a nimals utilized were either pituitary-intact rats or rats hypophysecto mized for 3 or 10 days. Hormone supplementation began at day 3 post-hy pophysectomy and continued until day 10 at which time all animals were sacrificed. The numbers of degenerating meiotic figures (metaphase to telophase of the first and second meiotic division) as expressed per Sertoli cell nucleus or nucleolus were not increased significantly 10 days after hypophysectomy as compared with animals hypophysectomized f or 3 days or with pituitary-intact controls. Exogenously administered testosterone and FSH had no effect on the numbers of degenerating meio tic germ cells in hypophysectomized animals. These data indicate that stage XIV metaphase to telophase spermatocytes are not hormone sensiti ve. However, it was determined that there were new cell types degenera ting at Stage XIV and I of the spermatogenic cycle. These were interph ase secondary spermatocytes and step 1 spermatids and were seen in sta ges XIV and I, respectively. These cell degenerations were found in lo w numbers in Stage XIV and I in either FSH-treated or testosterone-tre ated rats, suggesting their hormone sensitivity. Thus it is possible t hat Stages XIV and I are hormone sensitive stages. Since the progenito rs of these cells passed through Stage VII during a period of low horm onal levels, it is also possible that they degenerate in Stage XIV as the result of earlier hormone inadequacy.