抑郁模型大鼠海马区脑酪氨酸激酶受体B活性的变化

目的:从基因水平探讨抑郁症模型大鼠海马区脑酪氨酸激酶受体B活性(TrkB)的变化。方法:SD♂大鼠,分为正常对照组,7,14,21 d不同时程慢性应激刺激组,运用敞箱实验(Open-Field-test) 与糖水消耗量指标评定大鼠行为学改变,釆用免疫组织化学法检测TrkB蛋白表达,实时定量聚合酶链反应对TrkB进行定量分析。结果:实验前各组大鼠水平运动得分与垂直运动评分无差异,与正常对照组相比,7,14,21 d应激组水平﹑垂直运动得分均明显降低(P<0.05),各组间相比无明显差异(P>0.05)。 14,21 d应激组其糖水偏爱度持续减少(P<0.05),免疫组织化学检测结果显示,7,21 d应激组海马区TrkB表达与正常对照组明显降低(P<0.05), 7,21 d 应激组TrkB的mRNA含量亦明显低于正常组。结论:提示不同时程慢性应激刺激海马的神经再生变化与TrkB的中介机制相关联。

Changes of TrkB activities in hippocampus of rat model of depression

OBJECTIVE To investigate the changes of activity of tyrosine kinase receptor B (TrkB) in gene level in brain of rat model of depression.METHODS Male Sprague-Dawley rats were randomly divided into normal group,7d group,14d group and 21d group respectively receiving chronic unpredictable mild stress(CUMS).The sucrose consumption was detected and open-field-test was performed to assess rat behaviors.The expression of TrkB was detected by using immunohistochemistry assay and quantatitive analysis by real-time quantitative PCR method.RESULTS The difference was not significant in horizontal movement and vertical movement in each group before experiment,compared with normal control group,horizontal movement and vertical movement were significantly decreased after 7days,14days and 21days of CUMS (P<0.05),but no intra-group difference had been observed (P>0.05).The sucrose consumption was decreased consistently after 14days and 21days of CUMS (P<0.05).Compared with model group,after 7days and 21days of CUMS,immunohistochemistry technique and real-time quantitative PCR analysis showed that the expressions of TrkB decreased significantly in hippocampus (P<0.05),and TrkB mRNA contents after 7days and 21 days of CMSU were also evidently lower than that in normal gorup.CONCLUSION Changes of nervous regeneration in hippocampus after different days of CUMS are related with mediating mechanism of TrkB.