[Effect of HCG administration in the gossypol-treated male rats]

The effect of gossypol acetic acid (GAA) on the pituitary-Leydig cell axis was studied. Adult male Wistar rats were administered orally 5 mg/kg/day GAA for three weeks, 10 mg/kg/day GAA for three weeks or 20 mg/kg/day GAA for two weeks. Each group was treated for four days with saline or 500 IU human chorionic gonadotropin intraperitoneally injected. None of the rats died. The mean body weight in each group was increased, but the mean body weight gain in the 20 mg/kg group was significantly lower than that in the controls (p less than 0.01). There was no significant change in the weight of testes or epididymis in any group. The serum level of lactate dehydrogenase, follicle stimulating hormone and testosterone was significantly lower in the animals treated with 20 mg/kg/day GAA for two weeks than in the controls (p less than 0.05). No change was seen in other groups. The serum testosterone level after HCG stimulation (HCG 500 IU intraperitoneal injection for 4 days) was significantly lower in animals treated with 20 mg/kg/day GAA for two weeks (p less than 0.01). GAA is suggested to affect the pituitary-Leydig cell axis and directly inhibit Leydig cell function.