习得性无助大鼠脚底电刺激后海马c-FOS表达

Expression of c-FOS Protein in the Hippocampus of Rats with Learned Helplessness after Inescapable Foot Shock

目的:研究不可逃避的脚底电刺激对习得性无助大鼠海马神经元c-FOS表达的影响,以进一步探讨抑郁症的发病机制。方法:28只大鼠分为正常组6只,余22只采用不可逃避脚底电刺激制成习得性无助大鼠(实验组2)和非习得性无助大鼠(实验组1)动物模型,用特异抗体的免疫组织化学方法,观察正常组与实验组海马神经元c-FOS的表达情况。结果:实验组2在接受脚底不可逃避电刺激后,海马齿状回区内FOS蛋白的表达水平较实验组1和正常组低(P<0.05),而CA1和CA3区内FOS蛋白表达水平与实验组1和正常组差异无显著性意义。结论:FOS蛋白可以在基因表达水平反映神经元活性,习得性无助大鼠齿状回c-FOS蛋白表达下调提示该区域可能有细胞活性改变,此变化可能在习得性无助行为中有重要作用。

Objective： To study the effect of inescapable foot shock on the expression of c-FOS protein in the hippocampus of learned helplessness （LH） rats. Methods： Twenty-eight rats were divided into normal group （n=6）, experimental group i （n= 11, LH rats induced by inescapable fort shock） and experiment group 2 （n= 11, nonLH rats）. The distribution of c-FOS neurons in the hippocampus was observed in normal group and experimental groups by using immunohistochemical method. Results： In the experimental group 2, c-FOS-like immunoreactivity （FLI） in the hippocampus dentate gyrus was significantly lower than in the normal group and experimental group 1 （P〈0.05）. But FLI in the CA1 and CA3 area of the experiment groups 2 was no obvious difference with the other two groups. Conclusion： FOS protein is considered to be an indicator of activity at the level of gene expression. The decreased expression of c-FOS protein in dental gyrus of LH possibly indicates alterations of neuron activity, and it is important for the LH.