Ovarian dysfunction in neonatally thymectomized rats.

Abstract

The effect of neonatal thymectomy upon the reproductive function was examined infemale Wistar rats. After female pups were thymectomized within 48 hours of birth, the somatic growth was not inferior to that of controls after 18 days of age, but less than controls from 3 to 15 days of age (P<0.01 or 0.05). The day of vaginal opening in thymectomized rats (41.2±1.02) was similar to that of intact rats (39.9±0.78). The results of incidences of vaginal estrous and proestrous stageor estrous stage alone at 20-day in-tervals from 50 to 169 days of age in thymectomized rats indicated that the ovarian func-tion appeared to decline progressively after 90 days of age. Between thymectomized and intact rats, there was no significant difference in the weight of ovaries, uteri, pituitary gland, thyroid glands and spleen, except the weight of adrenal glands (P> 0.05) at 180 days of age. Histological findings in thymectomized rats indicated the hyperplasia of theinter-stitial cell elements and degeneration of follicles in the ovary and formation of marked cytoplasmic haloes in the basophilic cells of the pituitary gland.