经颅磁刺激对帕金森病模型大鼠运动诱发电位潜伏期的研究

目的：通过对帕金森病（PD）模型大鼠经颅磁刺激（TMS）运动诱发电位（MEP）皮层潜伏期（Lat）的测值以了解其随病情发展的变化情况。方法：健康雄性（SD）大鼠40只，随机分为2组：①PD模型组26只，②对照组（生理盐水组）14只。选取右侧黑质致密部（substantia nigra pars compacta，SNc）与中脑腹侧背盖（ventra tegmental area，VTA）为手术靶点，PD模型组注射6一羟基多巴胺（6-OHDA）制备PD动物模型，对照组注射同等体积的生理盐水。于注射前、注射后第1周、第3周末分别行双下肢TMS-MEP检查。结果：术后1周，PD组鼠左下肢Lat较对照组缩短（P〈0．05），PD组自身左右侧TMS-MEP比较，左下肢Lat较右下肢缩短（P〈0.05）；术前、术后第1周末、术后第3周末PD组大鼠左下肢Lat进行性缩短（P〈0.01），PD组大鼠右下肢及对照组大鼠左侧及右侧下肢Lat皆无显著变化（P〉0.05）。结论：PD模型大鼠损毁侧皮层兴奋性增加，且与症状严重程度有关。PD模型大鼠病情越重、病程越长，Lat缩短越明显。

Cortical latency of motor evoked potentials by transcranial magnetic stimulation for model rats with Parkinson's disease

Objective：To make clear if parkinson disease（PD） has cortical latency of transcranial magnetic stimulation（TMS）-motor evoked potential（MEP） abnormality and cortical latency（Lat） changes with the developing state of illness. Methods：Rats were randomly assigned into PD model group（n： 26） and the control group（n= 14）. The operated target was the right substantia nigra pars compacta（SNc） and right ventra tegmental area（VTA） ,which were injected with 2 μL（4 μg/μL 6-OHDA in PBS） solution of 6-OHDA in PD model group. Saline containing 2% vitamin C with isometry injected to the same location in the control group. Lat was examined before operation,and a week and three weeks after operation. Statistical analysis was performed by SPSS 11.5 software. Results： A week after operation, Lat of left lower limb was significantly tow in the PD model group（P〈0. 05） as compared with the control group. In the PD model group,Lat of left lower limb significantly lower than right ones（P〈0.05）. Three weeks after operation,Lat of left lower limb was significantly low in the PD model group（P〈0.05） as compared with the control group. And Lat of left lower limb significantly lower than right ones（P 〈0.01）. Conclusion： The cortex excitability increased. The worse the PD model state is the longer the course of disease PD model rats and the more obviously the cortical Lat is shortened.