Structural and functional changes in ovaries from adult mice treated with diethylstilboestrol in the neonatal period

Ovaries from 8-week-old female NMRI mice in different stages of the oestrous cycle, or from females neonatally treated with the synthetic oestrogen diethylstilboestrol (DES; 5-10(-6) micrograms daily for 5 days), were studied histologically and for the ability to synthesize steroids from [3H]pregnenolone in vitro. Daily doses of 10(-4) micrograms DES or higher resulted in absence of corpora lutea. In ovaries lacking corpora lutea, the interstitial tissue dominated and the cells in this compartment were large with a clear cytoplasm. The steroids synthesized in ovarian homogenates were separated with thin-layer chromatography. The homogeneity of the steroids was checked in recrystallization experiments. Daily doses of 5-10(-4) micrograms DES in the neonatal period resulted in pronounced deviations in the pattern of ovarian steroids synthesized as compared with control ovaries. In DES-exposed ovaries, the synthesis of androstenedione and, above all, progesterone was high while the synthesis of 17 alpha-hydroxyprogesterone and testosterone was reduced compared with controls. These results could argue for a difference in activities of 17 alpha-hydroxylase and 17 beta-ol-dehydrogenase in ovaries from DES-treated females compared with controls. After transplantation of DES-exposed ovaries to ovariectomized control females, the steroid pattern changed to that typical for control ovaries. Control ovaries transplanted to DES-treated females had a steroid pattern similar to that of DES-exposed ovaries.