运动训练对缺血再灌注大鼠纹状体中代谢型谷氨酸Ⅰ组受体基因表达的影响

The effect of treadmili training on metabotropic glutamate receptor of a rat model of middle cerebral artery occlusion

目的研究运动训练对缺血再灌注大鼠纹状体处Ⅰ组代谢型谷氨酸受体（mGluRⅠ）水平变化的影响，以探讨运动训练对缺血性脑梗死的保护机制。方法将2～3月龄雄性成年SD大鼠18只随机分为假手术组、缺血再灌注模型组（缺血再灌注组）和缺血再灌注后运动训练2周组（运动训练组），每组6只大鼠。于运动训练组运动训练2周后，3组大鼠同时断头取脑，采用逆转录-聚合酶链反应（RT-PCR）技术分析大鼠缺血部纹状体脑组织内的代谢型谷氨酸受体1型（mGluR1）和代谢型谷氨酸受体5型（mGluR5）的信使核糖核酸（mRNA）表达水平。结果缺血再灌注组大鼠纹状体mGluR1和mGluR5的mRNA升高明显（P〈0．01），运动训练组大鼠纹状体mGluR1和mGluR5的mRNA较缺血再灌注组有明显下调（P〈0．01）。结论运动训练可以使缺血再灌注大鼠Ⅰ组代谢型谷氨酸受体（mGluRⅠ）水平下调，这可能是抑制兴奋毒性谷氨酸的产生的重要机制之一。

Objective To observe the effect of treadmill training on metabotropic glutamate receptor of a middle cerebral artery occlusion model in rat and its underlying mechanisms. Methods Sprague-Dawley male rats of 2 or 3 months old were randomly divided into 3 groups ： a sham operation group, an ischemia-reperfusion group and a treadmill training group （ subject to 2 weeks of training after the isehemia-reperfusion）. All the animals were sacrificed after 2 weeks of training and their brains were sampled for measurement of the expression level of the striatum mGluR Ⅰ -mRNA, using RT-PCR technique. Results The striatum mRNA of mGluR1 and mGluR5 was significantly elevated in the ischemia-reperfusion group（ P 〈 0.01 ）, but treadmill training significantly suppressed the elevation of the expression of mRNA of mGluR1 and mGluR5 （P 〈 0.01 ）. Conclusions Treadmill training can significantly downregulate mGluR Ⅰ -mRNA expression. This might be one of the important mechanisms for inhibition of the excitatory glutamate production.