Effects of tripchlorolide on the epididymides and testes of rats.

Aim: To further evaluate the antifertility effects of tripchorolide, a derivative of triptolide produced at the extraction pro-cedure of Tripterygium wilfordii Hook. f., in male rats and to investigate its sites and possible mechanisms of action.Methods: In male rats, tripchlorolide was given by oral garage at a dose of 50 ug.kg～(-l).d～(-1) for 5 weeks, fertility wasassessed by mating tests, and biochemical indices and light microscopic observation of the epididymides and testes werealso performed. Results: Administration of tripchlorolide at 50 ugg.kg～(-l)-d～(-1) for 3 weeks did not influence the fertilityof male rats, but 5-week treatment rendered the rats infertile. The density and motility of spermatozoa collected fromcauda epididymides were reduced significantly. The epididymal weights, as well as the L-carnitine concentration and α-glucosidase content in the epididymal fluid were decreasd. There were no significant differences in α-glucosidase andacid phosphatase (ACP) in caput epididymal homogenates between the control and the experimental rats. Obvious mor-phological changes were observed in the epididymal spermatozoa, mainly including head and tail separation or acrosomecurving. Sloughed spermatids were found in the seminifeous and epididymal tubules. In tesficular homogenates,tripchlorolide had no influence on the lactate dehydrogenase-C_4 (LDH-C_4) and hyaluronidase activities. No apparentlesions were observed in the seminiferous and epididymal epithelium. Conclusion: At the dose level employed,tripchlorolide has a significant effect on the fertility in male rats and the primary sites of action may be spermatids and tes-ticular and epididymal spermatozoa. (Asian J Androl 1999 Sep ; 1: 121 - 125)