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[Influence of estradiol benzoate on the testis development of rats]
Quan Zhang1, Xin-hua Zhou, Xiao-bin Zhang
1Department of Urology, Renmin Hospital, Wuhan University, Wuhan, Hubei 430060, China. zhangquan1291@sina.com.cn
Objective:
To study the influence of estradiol benzoate (E2B) on the testis development of Sprague-Dawley (SD) rats.
Methods:
Newborn male SD rats were injected subcutaneously with E2B (0.2 mg/5 g body weight). At days 14, 21, 28, 42 and 56 after birth, the rats were sacrificed after anaesthesia, and their testes were taken out and weighed. The cranial and caudal SEH and TD were measured respectively, the TD/SEH ratio in each part of the testis and the caudal SEH/cranial SEH ratio were calculated, and different stages of spermatogenesis were analysed.
Results:
In the experimental group, the testis weight was significantly lower than that of the control (P < 0.01), the testes constantly remained in the abdominal cavity, and there was much fluid retention in the rete testis all the time. From day 21 on, the TD/SEH ratio in the cranial testis was much higher than in the control (P < 0.01), and so was the caudal SEH/cranial SEH ratio (P < 0.01). And spermatogenesis was obviously retarded as compared with the control (P < 0.01).
Conclusion:
Exposure of newborn male SD rats to E2B can cause fluid retention in the testis and cryptorchid, which in turn may retard spermatogenesis.
