[Effects of Hachimijiogan on hypothalamo-pituitary-testicular system]

Effects of Kampo (Chinese) drugs on hypothalamo-pituitary-gonadal system were investigated in immature male rats of Holtzman strain. Hachimijiogan(H), its components and Ninjin(N) were administered orally to the animals for 28 days, and the weight of the various organs, pituitary content of FSH, LH and PRL, and serum concentration of FSH, LH, PRL and testosterone were measured. H caused a significant increase in the weight of seminal vesicles while H, Sanyaku(S) and N caused a significant increase in the weight of the prostate, respectively. The pituitary content of FSH was significantly increased by H and S, respectively, while the testosterone concentration was significantly decreased by Jio, S and N, respectively. No increase in the weight of the prostate or seminal vesicles followed the administration of H, S and N to orchiectomied immature rats. This result clearly shows that these three drugs have no androgenic activity. After the administration of H to immature male rats, the character of dihydrotestosterone(DHT) receptor was studied by the DCC method. The number of binding sites of DHT receptor was significantly increased by 32% (p less than 0.001) by H. These results demonstrate that H has a stimulatory effect on androgen target organs through the increase in androgen receptor in these organs.