The estrogenic effect of Pueraria mirifica on gonadotrophin levels in aged monkeys.

We investigated the effect of Pueraria mirifica (PM) on gonadotrophin and estradiol levels in aged animals; nine menopausal cynomolgus monkeys were divided into three groups. Each group (n = 3) was fed with 10, 100, and 1000 mg/d of PM for 90 d. PM-10 induced the decrease of follicle stimulating hormone (FSH) levels on d 15-90 in one out of three monkeys. PM-100 and PM-1000 decreased FSH levels of all monkeys throughout the treatment period. After the treatment period, FSH levels continued to decrease for 5 and 10-20 d in PM-100 and PM-1000, respectively, and the levels rebounded in all groups thereafter. PM-10 decreased luteinizing hormone (LH) levels throughout the treatment period in one out of three monkeys and returned to the pretreatment levels immediately after stopping treatment. PM-100 and PM-1000 prominently decreased LH levels between d 10 and 90 during treatment and persisted until d 15-25 and d 20-30 for PM-100 and PM-1000, respectively, during the post-treatment period. Serum LH levels rebounded after returning to pre-treatment levels in a dose-dependent manner. Estradiol levels tended to decrease during the treatment period in all groups. The daily feeding of PM suppressed gonadotrophin levels in aged menopausal monkeys based on dose. Moreover, they can be recovered, and there is a direct correlation between dosage and recovery time. PM may be effective as an alternative medicine in menopausal women because the effects are not permanent.