p-Tau蛋白在抑郁症大鼠海马组织中的表达

Expression of p-Tau protein in hippocampus tissue of rats with depression

目的:观察抑郁症大鼠海马组织中磷酸化微管相关蛋白Tau(p-Tau)的表达水平,探讨p-Tau与抑郁症的关系。方法:40只大鼠随机分为对照组(n=20)和模型组(n=20),模型组大鼠采用慢性不可预见性温和应激(CUMS)建立大鼠抑郁症模型,对照组大鼠每天抓取1次。分别采用糖水偏好实验、旷场实验和Morris水迷宫实验检测对照组和模型组大鼠行为学表现;尼氏染色观察大鼠海马神经元形态学;对照组和模型组造模后1、7、14和28d分批处死大鼠,采用Western blotting法检测大鼠海马组织中p-Tau蛋白表达水平。结果:糖水偏好实验,模型组大鼠糖水消耗量和糖水偏好百分比低于对照组(P<0.01);旷场实验,模型组大鼠行走总路程、中央活动时间、直立次数和修饰行为次数少于对照组(P<0.01);Morris水迷宫实验,模型组大鼠平均逃避潜伏期长于对照组(P<0.01);CUMS后1d,模型组大鼠海马组织中p-Tau蛋白表达水平低于对照组(P<0.01),7d后开始高于对照组(P<0.05),14d时大鼠海马组织中p-Tau蛋白表达水平最高(P<0.01)。结论:抑郁模型大鼠海马组织中p-Tau蛋白表达水平先降低后增高,这可能影响微管的稳定性,破坏细胞骨架稳态,从而导致海马神经元的结构改变。

Objective To observe the expression level of the phosphorylated microtubule-associated protein Tau（p-Tau）in the hippocampus tissue of the rats with depression,and to explore the relationship between p-Tau and depression.Methods 40 rats were randomly divided into control group（n=20）and model group（n=20）.The depression models of rats were established by chronic unpredictable mild stress（CUMS）,and the rats in control group were caught once a day.The behavior examination was carried out in control group and model group by sucrose preference test,open field test,and Morris water maze.The morphology of hippocampal neurons of the rats was observed by Nissl staining.At the 1st,7th,14 th,and 28 th day after CUMS,the rats in control group and model group were executed in batches and the expression levels of p-Tau protein in the hippocampus tissue of the rats were detected by Western blotting method.Results The sucrose preference test results showed that the sucrose consumption and the percentage of the sucrose preference of the rats in model group were lower than those in control group（P〈0.01）;the open field test results showed the overall walking distance,the central activity time,the up-right times,and the grooming behavior of the rats in model group were lower than those in control group（P〈0.01）;the Morris water maze results showed the average escape latent period of the rats in model group was higher than that in control group（P〈0.01）.The expression level of p-Tau protein in the hippocampus tissue of the rats in model group was lower than that in control group 1dafter CUMS（P〈0.01）,and was higher than that in control group after 7d（P〈0.05）;the expression level of p-Tau protein in the hippocampus tissue of the rats in model group was the highest 14 dafter CUMS（P〈0.01）.Conclusion The expression level of p-Tau protein in the hippocampus tissue of the rats with depression is decreased firstly and then increased,which may affect the stability of microtubule and destroy the steady state of cytoskeleton,thus leading to the structural changes of the hippocampal neurons.