Objective To determine whether co-administration of mixed steriod hormones can enhance the restoration of spermatogenesis damaged by gossypol acetic acid （GA）. Methods Adult male Wistar rats were treated daily for 8 weeks with GA at 50mg/kg plus testosterone undercanoate （100 mg/kg）/desogestrel （0.125 mg/kg）/mini-dose ethinylestradiol （0.025 mg/kg） （TU/DSG/EE）, followed by a period of 9 weeks for recovery. Control animals were administered the same dose of GA or TU/DSG/EE, and vehicle, respectively. Testis weight, testicular sperm head count and histological analysis were utilized to assess the spermatogenesis. Results At the end of the 9-week reovery period, in rats given GA alone, spermato- genesis steadily declined. However, when rats received combined hormone adminis- tration during GA treatment, this decline was prevented and an complete recovery of spermagenesis occurred. The haploid spermatids and spermatocytes was not to be protected but to be more aggravatedly damaged. The excellent recovery must have resulted from that the hormone treatment could protect the ability of stem spermatogonia to differentialte and evolve progressively into mature spermatozoa. In addition, the concentrations of serum LH, FSH and intratesticular testosteron （ITT） notably decreased after 2 or 8 weeks of treatment, then returned to control levels at the end of 9-week recovery period.Conclusion Steriod hormone treatment enhaces the recovery of spermatogenesis through preventing seminiferous epithelim from GA-induced destructive damage in rats. The enhanced recovery was closely associated with the marked suppression in intratesticular testosteron （ITT）.
Zhan-jun YANGFang SONGZe-jun WANGYan SHIGang FANGHe WANG
