Response of testis to androgen and gonadotropins in neonatally estrogenized and androgenized mice.

Abstract

Male mice of the C3H/Tw stain were given 15 daily injections with estradiol-17β(E), 30μg/day, or testosterone propionate (TP), 50μg/day for the first 10 days and 100μg/day for the following 5 days, from the day of birth, which were followed by 30 daily injections with TP, TP plus PMS or PMS plus HCG. Daily doses of hormones were increased with advancing age, 50μg (for the first 5 days), 100μg (for the middle 15 days) and 200μg (for the last 10 days) for TP, and 10 IU (for the first 5 days), 15 IU (for the next 15 days) and 30 IU (for the last 10days) for gonadotropins. The control mice received oil and saline after neonatal treatment with E or TP. When sacrificed on the day following the last injection, the controls had small testes without spermatogenesis and underdeveloped seminal vesicles. Especially, in one of the neonatally estrogenized mice, one of the testes was markedly damaged. Injections of TP, TP plus PMS or PMS plus HCG for 30 consective days restored the testicular activities in neonatally androgenized mice. Although the testes were smaller than in the controls given neonatal oil injections, active spermatogenesis was going on in a majority of the seminiferous tubules. By contrast, injections of TP and/or gonadotropins failed to restore normal spermatogenesis in a majority of the neonatally estrogenized mice, about 20 to 30% of the animals having one or both testes severely damaged. However, interstitial cells of the testes underwent hypertrophy and hyperplasia in response to the gonadotropin injections in animals given either E or TP neonatally, although the stimulation was slight in those given neonatal TP followed by TP plus PMS. The seminal vesicles grafted from infantile males into neonatally estrogenized mice were androgenically stimulated when recovered after injections of gonadotropins for 25 days. Leydig cells of the hosts' own testes were hypertrophied. However, as in neonatally estrogenized mice given injections of androgen, the hosts' glands remained atrophic, containing no secretion in the lumen.