The Effect Of Embryonic BPA Exposure On Histone Acetylation Of Male Young Rats' Hippocampus

[Objective]BPA(Bisphenol A,BPA), being one of the world's most widely used industrial chemical, is a kind of estrogen effects of environmental endocrine disruptors and the important raw material for production of polycarbonate, thermal paper and epoxy resin. In this paper, we studied the effect of embryonic BPA exposure in the hippocampus of rat on the expression of histone acetylation/deacetylation enzyme gene and protein level, in order to explore the dynamic process of histone acetylation caused by bisphenol A, and to explore the neurotoxic effect of bisphenol A.[Method] Sprague-Dawley rats were given BPA, concentrations of which were 0.05,0.5,5,50 mg/kg body weight (BW) per day since 9 days after pregnancy (E9) to 20 days (E20). Male rats at 21 days (PND21) and 70 days of postnatal were used for subsequent tests. We detected the brain tissue morphological structure of male young rat, histone acetylation related enzymes (HDACs and HATs) mRNA and protein expression by using toluidine blue staining, Real-time PCR, Western blotting technology.[Result](1) Embryonic BPA exposure affected the hippocampal tissue morphological changes of male young rat:reduced the numbers of nissl bodies (nerve cells), smaller volume, shrinkage of neurons. (2) Embryonic BPA exposure affected the expression of postnatal male young rat hippocampus of histone acetylation enzyme. Real-time PCR experimental results show that BPA exposure group of HDAC1 and HDAC3mRNA expression level decreased significantly, HDAC2 mRNA expression level increased significantly, compared with the control group. Western blotting test results denoted:BPA exposure group, compared with control group, HDAC1, HDAC3 and H3 protein expression levels, HDAC2 and Ac-Histone3 protein expression level increased significantly. (3) Embryonic BPA exposure significantly increased the total histone acetylation enzyme of postnatal male young rats'hippocampal.[Conclusion] The experimental results revealed that embryonic BPA exposure reduced the learning and memory ability of postnatal male young rats, the molecular mechanisms involved in epigenetic changes in the level of histone acetylation, suggesting BPA affected the central nervous system and the complexity of behavioral development.