Effects of Hachimijiogan, a Kampo powder, on epididymidis sperm characteristics in healthy male rats.

Purpose: Hachimijiogan (HJG, Rehmannia Eight Formula), a kidney-replenishing Kampo formula, is clinically known to be effective in the treatment of male infertility with oligozoospermia. The purpose of this study was to evaluate the effect of HJG on the epididymal sperm characteristics and related serum hormone changes in rats in an attempt to determine its mechanism. Methods: Male Wistar-Imamichi rats (233.4 ± 5.2 g, nine weeks old) were assigned randomly to four groups (n = 6 for each group). Apart from one control group treated with distilled water, the other groups were administered HJG consecutively for 9-11 days with doses of 250, 500 and 1,000 mg/kg. After the last administration the caude epididymides were quickly removed under anesthesia for assessing sperm characteristics. Additionally, the testes, seminal vesicles, prostate and adrenal glands were removed surgically and their wet weights measured. Results: Results showed that HJG increased sperm numbers and motility as well as the weights of seminal vesicles and adrenal glands at lower doses. Moreover, HJG decreased serum levels of testosterone and luteinizing hormone while increasing follicle-stimulating hormone levels. Conclusions: Our findings may support the conclusion that a lower dosage of HJG has an effect on improving local spermatogenous environments by activating adrenal functions and/or promoting local androgen activity.