ABSTRACT
Objective To investigate the effects of gonadotropin releasing hormone agonist (GnRH- a) and antagonist (GnRH-ant) on cyclophosphamide (CTX)-induced ovarian damage in rats.Methods Seventy-two Sprague-Dawley female rats were divided randomly into six groups,which received normal saline (NS),CTX,GnRH-a+NS,GnRH-a+CTX,GnRH-ant+NS,and GnRH-ant+CTX respectively.Levels of serum follicle-stimulating hormone (FSH),luteinizing hormone (LH) and estradiol (E_2) were measured successively by the enzyme-linked immunosorbent assay method,and half of the rats were killed in the first week and between the fourth and the fifth week after stop of medication,respectively to compare the weight of the ovaries and the number of the primordial follicles and the growth follicles.Results (1) Throughout experiment,the serum levels of FSH,LH and E_2 of the control group fluctuated slightly,while those in the CTX group kept rising.During medication treatment,compared with the control group[(118?16) ?g/L, (350?35) ?g/L] and the CTX group[(113?15) ?g/L,(289?42) ?g/L],the concentrations of LH [(42 ?8)-(47?7) ?g/L,(31?5)-(36?7) ?g/L] and FSH [(124?45)-(136?32)?g/L,(178 ?54)-(198+27)?g/L] in the GnRH-a groups and the GnRH-ant groups were maintained at low levels significantly and the levels of LH in the GnRH-ant groups were significantly lower than that in the GnRH-a groups,but the levels of FSH in the GnRH-ant groups were significantly higher than that in the GnRH-a groups(P0.05),but the levels of FSH,LH and E_2 of the GnRH-ant+CTX group rose obviously and were similar to the levels of the CTX group,especially the FSH,and the levels of LH and FSH of the GnRH- ant + CTX group [(156?12) ?g/L,(520?44) ?g/L] and the CTX group [(178?18) ?g/L,(546?36) ?g/L] were significantly higher than that of the other four groups [(121?15)-(132?13) ?g/L,(335 ?35)-(359?26) ?g/L] at the 4~(th)-5~(th) week after stop of treatment(P0.05),but the number of all kinds of follicles declined significantly in the GnRH-ant+CTX group[(195?15),(36?12)] and the CTX group [(212?11),(36?9)] compared to the other four groups[(302?15)-(690?43),(44?12)-(58?11),P