电针对脑缺血-再灌注损伤大鼠海马神经元PGC-1α表达及线粒体酶活性的影响

Effects of electroacupuncture therapy on PGC-1α mRNA expression and mitochondrial enzyme activity in hippocampuses after cerebral ischemia-reperfusion injury in rats

目的观察不同强度电针对脑缺血-再灌注(I-R)损伤大鼠海马神经元过氧化物酶体增殖物激活受体γ辅激活因子1α(PGC-1α)表达及线粒体酶活性的影响。方法 40只雄性SD大鼠随机均分为假手术组(S组)、脑I-R组、脑I-R+E1组、脑I-R+E2组和脑I-R+E3组。采用大脑中动脉阻塞法诱导出大鼠脑缺血模型。I-R+E1组、I-R+E2组和I-R+E3组分别于模型制备后1和12h实施电针,每次20分钟,电流强度分别为5、3和1mA。再灌注24h时,测定脑组织琥珀酸脱氢酶(SDH)和细胞色素C氧化酶(COX)活性,RT-PCR检测PGC-1αmRNA的表达。结果与S组比较,I-R组海马组织神经元PGC-1αmRNA表达下调,线粒体SDH和COX活性降低(P<0.05);与I-R组比较,I-R+E1组、I-R+E2组和I-R+E3组线粒体COX活性均升高,I-R+E2组海马组织神经元PGC-1αmRNA表达上调,线粒体SDH活性升高(P<0.05或P<0.01)。结论电流强度3mA的电针可通过诱导PGC-1αmRNA表达,上调PGC-1α介导的呼吸链酶的活性,减轻大鼠脑I-R损伤。

Objective To observe the effects of electroacupuncture therapy with different intensities on the expression of peroxisome proliferator-activated receptor y coactivator-lα（PGC-lα） mRNA and mitochondrial enzyme activities in the hippocarnpus after cerebral ischemia-reperfusion （I-R） injury in rats. Methods Forty male SD rats were equally randomized into five groups of A （sham operated）,B（eerebral I-R injury model established by middle cerebral artery occlusion）,C, D and E（given electroacupuneture therapy with 5 mA, 3 mA and 1 mA on Baihui, Mingrnen and Zusanli for 20 minutes at 1 and 12 h after cerebral I-R injury）. The activities of SDH and COX and the expression of PGC-lα mRNA in the hippoeampus were detected by chemical chromometry and RT-PCR at 24 h after cerebral I-R injury. Results Compared with group A, the expression of PGC-lα mRNA and activities of SDH and COX in the hippocampus were decreased in group B（P〈0. 05）. Compared with group B,COX activity in the hippocampus was increased in groups of C,D and E,and the expression of PGC-la mRNA and SDH activity in the hippocampus were increased in group D （P〈0. 05 or P〈0. 01）. Conclusion The electroacupuncture therapy with 3 mA intensity can alleviate the cerebral I-R injury in rats through upregulation of the expression of PGC-lα mRNA and the activities of SDH and COX.