Investigation on the sex difference in the epigenetic regulation of the CRF gene in the hypothalamus

男性和女性对各种压力的反应不同。本研究通过对雄性和雌性大鼠下丘脑室前核（PVN）CRF基因启动子的表观遗传状态进行研究，探讨应激反应性别差异的可能机制。PVN基础CRF表达无性别差异，但束缚应激引起的CRF表达增加，雌性大于雄性。关于PVN中CRF启动子区域的表观遗传状态，在DNA甲基化谱中没有观察到性别差异，而束缚应激后组蛋白乙酰化水平在女性中倾向于更高。 这些结果表明CRF表达的性别差异与组蛋白修饰有关，而与DNA甲基化无关。

Male and female respond differently to various stress. In this study, the epigenetic status of the CRF gene promoter in the praventricular nucleus (PVN) of the hypothalamus of male and female rats were investigated in order to elucidate the underlying mechanisms of the sex differences in the stress response. No sex difference was observed in basal CRF expression in the PVN, whereas the restraint-stress induced increase in the CRF expresson in the female rats were larger than that of the male. Regarding the epigenetic status of the CRF promoter region in the PVN, no sexdifference was observed in the DNA methylation profile, whereas the level of histone acetylation after restraint stress tends to higher in the female. These results indicate the involvement of the histone modification but not DNA methylation in sexdifference in the CRF expression.