Antifertility effects of gossypol in male hamsters.

In the male hamster, administration of 10 or 15 mg/kg/day of gossypol for 5 weeks did not alter the serum concentration of testosterone (T), prolactin (PRL), and luteinizing hormone (LH) or fertility. However, the total sperm population was significantly reduced in the males treated with 15 mg/kg/day of gossypol, and total sterility occurred within 8 weeks. On the other hand, males treated with 10 mg/kg/day of gossypol were sterile after 10 weeks of treatment. The T and total sperm population along the reproductive tract in these infertile males was significantly reduced. During the treatment period no change in body weight or weight of testes or seminal vesicles was observed. A full regaining of fertility, serum T level, and sperm population to the normal range were recorded within 8 nd 14 weeks (15 and 10 mg/kg/day, respectively) after the cessation of treatment.