目的 探讨慢性束缚应激对小鼠海马N6-甲基腺苷（m6A）及相关酶表达影响。   方法 将20只C57BL/6J雄鼠随机分成对照（control）组、慢性束缚应激模型（CRS）组；给予CRS组小鼠3周慢性束缚应激建立小鼠焦虑模型，采用旷场实验和高架十字迷宫实验检测各组小鼠焦虑样行为变化；采用免疫组织化学法和m6A RNA 甲基化检测试剂盒检测小鼠海马m6A的表达变化；采用Western blotting和Real-time PCR方法分析海马m6A相关酶表达变化。  结果 1.小鼠焦虑相关行为学检测结果显示，与control组相比，CRS组小鼠在旷场内框停留时间明显下降（P< 0.01）；高架十字迷宫开放臂探索时间减少（P<0.0001）；2. m6A RNA 甲基化检测试剂盒检测结果显示，与control组相比，CRS组小鼠海马m6A含量明显减少（P<0.05）；免疫组化结果显示，与control组相比，CRS组小鼠海马m6A阳性产物明显减少（P<0.001）；3. PCR结果显示，与control组相比，CRS组小鼠海马去甲基化酶间变性淋巴瘤激酯B（AlkB）同源蛋白5（ALKBH5)（P<0.001）、脂肪和肥胖相关蛋白（FTO）表达显著上调（P<0.05）；甲基化酶Wilms肿瘤蛋白1相关蛋白（WTAP）（P<0.05）表达显著下调；m6A甲基化结合蛋白YTH结构域家族蛋白3（YTHDF3）（P<0.05）和YTH结构域蛋白2（YTHDC2）（P<0.01）表达显著上调。Western blotting 结果显示，与control组相比，CRS组小鼠海马去甲基化酶ALKBH5（P<0.05）、FTO（P<0.05）表达显著上调；甲基化酶WTAP（P<0.01）表达显著下调；m6A甲基化结合蛋白YTHDF3（P<0.01）和YTHDC2（P<0.05）表达显著上调。    结论 在慢性束缚应激所致小鼠焦虑与海马m6A表达下调有关，其机制可能与m6A甲基化酶WTAP表达下调或去甲基化酶ALKBH5和FTO表达上调相关。 

Objective  To investigate the effect of chronic restraint stress on the expression of N6-methyladenosine (m6A）and related enzymes in the hippocampus of mice.     Methods Twenty C57BL/6J male mice were randomly divided into control group and chronic restraint stress (CRS) group, the model group was given for 3 weeks chronic restraint stress to establish a mouse anxiety model. Open field test and elevated plus maze test were used to detect anxiety-like behavior; Immunohistochemistry and m6A RNA methylation assay were used to detect the expression changes of mouse hippocampal m6A; Western blotting and Real-time PCR were used to analyze hippocampal m6A related enzymes expression.     Results  1.The behavioral results showed that, compared with the control group, the CRS group showed significantly reduced time spent in the center of the open field(P<0.01), the CRS group showed significantly reduced exploration time in the open arm of elevated plus maze (P<0.0001); 2. Immunohistochemical results showed that, compared with the control group, the hippocampal m6A content in the CRS group reduced significantly (P<0.001); The results of the m6A RNA methylation assay showed that, compared with the control group, the CRS group showed significantly reduced amount of hippocampal m6A(P<0.05); 3. Real-time PCR results showed that the expression of hippocampal demethylase anaplastic lymphoma kinase B(AlkB) homolog 5(ALKBH5) (P<0.001) and fat mass and obestity associated protein(FTO) (P<0.05) in the CRS group significantly up-regulated, the expression of methylase Wilms’tumour 1-associating protein(WTAP) (P<0.05) was significantly down-regulated compared with the control group; The expression of m6A methylation binding protein YTH domaincontaining family protein 3(YTHDF3) (P<0.05) and YTH domaincontaining protein 2(YTHDC2)(P<0.01) was significantly up-regulated. Western blotting  result  showed that, compared with the control group, the mouse hippocampal demethylase ALKBH5 (P<0.05) and FTO (P<0.05) expression in the CRS group significantly up-regulated, the expression of WTAP (P<0.01) was significantly down-regulated; m6A methylation binding protein YTHDF3 (P<0.01) and YTHDC2 (P<0.05) were significantly up-regulated.     Conclusion In the anxiety model induced by chronic restraint stress, the expression of m6A in the hippocampus of mice is down-regulated. The mechanism may be related to the up-regulation of the m6A demethylase ALKBH5 and FTO or the down-regulation of the methylase WTAP.