The influence of human menopausal gonadotropin, natrium fluoride and cyproterone acetate on the spermatogenesis in immature rats.

Human menopausal gonadotropin (HMG), natrium fluoride (NaF) and cyproterone acetate (CYA) were applied to immature male rats between the 26th and 32nd day of life and histological examination was performed in testes of 33rd-day-old rats. HMG treatment alone slightly influenced the spermatid completion process, while NaF evidently increased frequency of occurrence of various seminiferous tubules containing spermatids. CYA alone damaged the spermatid completion process (especially the cap-phase of spermiogenesis), produced a degeneration of meiotic spermatocytes, and decreased the tubular diameter. Those changes were prevented by addition of HMG to the CYA treated animals. The results suggest a possible regulatory role of FSH at the end of the first meiosis, and, also, in the progression of spermiogenesis. The mechanism of action of NaF may be hypothetical, but it probably consists of direct action on the seminiferous epithelium level.