低频经颅磁刺激对VCI大鼠学习记忆及海马突触可塑性的影响

摘要

目的 研究低频经颅磁刺激(rTMS)对血管性认知障碍(VCI)大鼠学习记忆的影响机制.方法 健康雄性SD大鼠60只,随机分为正常对照组(normal)、假手术组(sham-operated)、模型组(VCI)、rTMS刺激组(VCI +rTMS).Morris水迷宫进行行为学认知实验,电生理学测定大鼠脑片海马齿状回(DG)在高频刺激下(HFS)诱发的突触长时程增强(LTP)现象.结果 水迷宫实验中,第4天起rTMS刺激组大鼠逃避潜伏期与模型组相比,差异有统计学意义(P<0.05);电生理实验中,10 min时rTMS刺激组PS幅值升高,LTP幅值变化率与模型组相比,差异有统计学意义(P<0.01).结论 rTMS增加VCI大鼠海马区LTP效应从而增强突触的功能可塑性,改善VCI大鼠的认知功能.%Objective To study the effect of low frequency repetitive transcranial magnetic stimulation (rTMS) on learning and memory and the long-term potentiation (LTP) in hippocampus of vascular cognitive impairment(VCI) rats.Methods Sixty male SD rats were randomly divided into normal group, sham-operated group, model group(VCI), control treatment group(VCI+ rTMS).The spatial learning and memory ability of rats was measured by Morris water maze.Electrophysiological recordings were conducted to detect the effects of repetitive transcranial magnetic stimulation(rTMS)on phenomena of synaptic transmission long-term LTP in dentate gyrus (DG) of hippocampus slices under the high frequency stimulation (HFS).Results In the escape latency after the 4th days, the rTMS treatment group was shortened to the model group (P<0.05).10 minutes later, the PS amplitude of the control treatment group increased and the LTP was enhanced, there were significant difference compared with model group(P<0.01).Conclusion The rTMS can improve VCI model rats learning and memory ablity by means of enhancing hippocampal LTP and the function of synaptic plasticity.