双酚A暴露对大鼠脾脏结构及雌激素受体-α表达的影响

Effect of Bisphenol A on the Structure of Spleen and the Expression of ER-α in Rats

目的研究双酚A暴露对大鼠脾脏结构及雌激素受体-α表达的影响。方法将40只健康4周龄SPF级F344大鼠按体重随机分为对照组(玉米油)和低(4mg/kg)、中(40mg/kg)、高剂量(400mg/kg)双酚A染毒组,每组10只,雌雄各半。采用灌胃方式进行染毒,灌胃剂量为5ml/kg,每天1次,连续染毒17周。染毒结束后,处死动物,取脾脏,称重,计算脾脏系数。观察脾脏组织形态学的改变,采用Western杂交方法测定ER-α表达的变化。结果与对照组相比,高剂量双酚A染毒组大鼠体重降低,差异有统计学意义(P<0.05)。随着双酚A染毒剂量的升高,脾脏白髓减少,脾小体缩小。各组大鼠脾脏重量和脾脏指数间比较,差异均无统计学意义(P>0.05)。与对照组相比,高剂量组雄性大鼠脾脏ER-α表达减少,雌性大鼠表达增加,差异均有统计学意义(P<0.01)。结论双酚A能够与靶细胞上的雌激素受体结合,模拟或拮抗雌激素的生理作用,改变脾脏的生长、发育及生理功能。

Objective To study the effect of bisphenol A on the structure of the spleen and the expression of ER-α in F344 rats. Methods Fisher 344 rats were randomly divided into control, low-dose, moderate-dose and high-dose groups, 10 in each and treated with bisphenol A through gavage at the doses of 4 mg/kg,40 mg/kg and 400 mg/kg respectively, once a day for 17 consecutive weeks. In the end of the experiment, the pathological examination of the spleen was done and the expression of ER-α was detected by western blotting. Results Compared with the control,the weight of high dose group decreased （P〈0.05）. The white pulp of spleens reduced and splenic corpuscle shrunk in the experimental groups, but no any change was observed in spleen weight and spleen index. The expression of ER-α decreased in male rats of high dose group but increased in female （P〈0.01）. Conclusion Bisphenol A can bind to the estrogen receptor in target cells and simulate or antagonize the effect of estradiot, which will induce changes in the development and function of target organ.