大豆黄酮对雄性大鼠生殖器官生长发育的影响

目的:探讨植物雌激素大豆黄酮对大鼠睾丸和附睾生长、发育的影响。方法:10周龄(成年早期)和4周龄(青春期)SD雄性大鼠各30只,分别分为5组:正常对照组,阳性对照组、低、中、高剂量大豆黄酮组,6只/组,分别给予生理盐水、0.1mg/kg己烯雌酚,2、20、100mg/kg大豆黄酮灌胃,连续90d,观察睾丸、附睾指数及体重的变化;HE染色观察睾丸、附睾等组织结构的改变。结果:在成年早期大鼠中,各剂量大豆黄酮组大鼠的体重、睾丸和附睾指数与正常对照组均无显著差异(P均>0.05);在青春期大鼠中,各剂量大豆黄酮组大鼠的附睾指数与正常对照组亦无显著差异(P均>0.05);而高剂量组大鼠的睾丸指数(3.21±0.07)显著低于正常对照组(3.71±0.32,P<0.05),中、低剂量组与正常对照组差异无显著性(P均>0.05);中、低剂量组大鼠的体重与正常对照组无显著性差异(P均>0.05),而高剂量组的体重则显著低于正常对照组(P<0.05)。HE染色结果显示青春期及成年早期大鼠摄入各剂量大豆黄酮对附睾组织结构无明显影响,而摄入高剂量大豆黄酮可使青春期大鼠睾丸发育迟缓,出现不同程度生精障碍。结论:青春期摄入高剂量的大豆黄酮对SD大鼠睾丸生长发育及组织结构有一定影响。

High-dose Daidzein Affects Growth and Development of Reproductive Organs in Male Rats

OBJECTIVE: To explore the effect of the phytoestrogen daidzein on the growth and development of the testis and epididymis in male SD rats. METHODS: Thirty 10-week old (early adult) and 30 4-week old (pubertal) male SD rats were included in the study, each age group equally divided into 5 subgroups: normal control, positive control, low-dose, medium-dose and high-dose. The normal and positive control groups were given 1 ml distilled water and the same amount of distilled water containing diethylstilbestrol (DES) at the dose of 0.1 mg/kg, and the low-, medium- and high-dose groups administered daidzein in the dose of 2mg/kg, 20 mg/ kg and 100 mg/kg, respectively, all by gavage for 90 days. Observations were made on the changes in body weight and testicular and epididymal indexes, as well as on the structural changes of the testis and epididymis by H&E staining. RESULTS: The early adult rats showed no significant differences in body weight and testicular and epididymal indexes between the claiclzein groups and the control (P > 0.05), nor did the pubertal rats in epididymal index (P > 0.05). The testicular index differed significantly between the high-dose group (3.21 +/- 0.07) and the normal control (3.71 +/- 0.45) (P < 0.05). The body weight reduced markedly in the high-dose group (P < 0.05), but with no significant differences between the normal control and the other two dose groups (P > 0.05). No obvious changes were observed in epididymal morphology in all the daidzein groups of the early adult and pubertal rats, but high-dose daizein resulted in smaller testes and impaired spermatogenesis. CONCLUSION: The phytoestrogen daizein, administered in a high dose, could delay the growth and development of the testis and induce structural changes of testicular tissues in pubertal SD rats.