Protective effect of gonadotropin-releasing hormone analog on the ovarian reserve in rats receiving cyclophosphamide treatment

OBJECTIVE: The aim of the study reported here was to investigate the protective effect of gonadotropin-releasing hormone analog (GnRHa) against cyclophosphamide (CTX)-induced gonadotoxicity. METHODS: Eighty Fischer 344 rats were divided randomly into four groups (20 per group). One group received normal saline, one GnRHa, one CTX, and one GnRHa+CTX. Several parameters were used to observe the ovarian reserve, including ovary weight, follicle number and diameter, concentrations of estradiol (E(2)) and follicle-stimulating hormone (FSH), and expressions of sex hormone receptors. RESULTS: When treatment was finished, the number of small follicles in the GnRHa+CTX group was significantly higher than in the CTX-alone group. Thirty days after treatment, the ovary weight, percentage of small follicles, mean follicular diameter, and serum concentrations of E(2) and FSH in the GnRHa+CTX group all recovered, approaching normal levels. Sex hormone receptors did not show significant differences between the four groups. CONCLUSION: Combination treatment with GnRHa could prevent CTX-induced damage to ovarian reserve.