围生期双酚A暴露对断乳期雄性子代脑芳香化酶表达的影响

Effects of perinatal exposure to BPA on expression of P450arom in cerebral tissues of male offsprings during weaning period in rats

目的:研究围生期双酚A暴露对断乳期雄性子代大鼠脑中芳香化酶P450(P450arom)表达的影响,探索双酚A影响脑发育的机制。方法:对母鼠从妊娠第11d直至产后断乳期(即出生后第21d,postnatalday21,PND21)给予双酚A(BisphenolA,BPA)2,20,100mg/kg。各组在断乳期PND21取雄性子代大鼠断头处死,迅速取脑组织进行免疫组织化学染色检测P450arom表达。结果:免疫组织化学染色结果显示,P450arom在大鼠海马和大脑皮层都有表达;对结果进行灰度值分析显示,高剂量组和中剂量组雄性子代大鼠断乳期P450arom在海马CA3区表达的灰度值分别为143.43和130.76,与对照组179.4612比较,有统计学意义;高剂量组雄性子代大脑皮层P450arom的灰度值为185.21,与对照组196.88比较,有统计学意义。结论:围生期暴露于BPA可使断乳期雄性子代脑中P450arom蛋白表达增加,这可能是影响发育机制的途径之一。

Objective. To investigate the expression of P450 aromatase in cerebral tissues of F1 generation SD rats during weaning period and to explore the effects of BPA on the brain development. Methods. Pregnant SD rats had been given BPA 2, 20 or 100 mg/kg body weights per day by garage, respectively, from the gestation day 11 throughout the period of lactation to the postnatal day 21 when their offsprings were weaned. All twenty - four F1 male offsprings from four groups, six ones every group, were killed at the weaning day（ postnatal day 21 ）. Their brains were removed and used to immunohistochemieal analysis.Results. The results of immunohistoehemieal stain showed that P450arom protein was expressed in both CA3 of hippocampus and cerebral cortex. The means of P450arom grey level were 143.43 in high - dose group and 130. 76 in middle - dose group in CA3 of hippocampus, respectively. The mean of P450arom grey level were 143.43 in high - dose group in cerebral cortex and was different significantly from that of the control group （185.21）. Conclusion： It is suggested that the prenatal exposure to BPA can increase the expression of P45arom protein in cerebral tissues, which may be one of the mechanism that BPA affect brain development.