Effects of Cyproterone Acetate, a Potent Antiandrogen, on the Preovulatory Follicle

Abstract

The effects of cyproterone acetate, a potent antiandrogen, on preovulatory follicles were studied both in vivo and in vitro. In vivo administration of cyproterone acetate induced acid phosphatase activity and reduced mitosis within the granulosa cell layer, accelerated the rate of atresia and subsequently transformed the preovulatory follicle into an ovarian cyst. Serum LH levels were not altered, but serum FSU levels were initially suppressed by cyproterone acetate treatment. In vitro, cyproterone acetate reduced the number of granulosa cells incorporating [³H]-thymidine by 50%. These observations suggest that androgens are involved in maintaining the preovulatory follicle and that their action is mediated in part by a direct intraovarian mechanism.