运动训练对大鼠脑梗死后肢体功能和GAP-43、MAP-2表达水平的影响

目的:研究运动训练能否促进大鼠局部脑缺血再灌注后的功能恢复并从神经可塑性角度探讨其机理。方法:线栓法制作Wistar大鼠大脑中动脉闭塞再灌注(MCAO)模型,随机分为运动组、对照组、假手术组及正常组,运动组术后24h起每天游泳10min,采用行为测试试验评分观察肢体功能恢复情况,免疫组化法观察脑缺血周边区生长相关蛋白-43(GAP-43)和微管相关蛋白-2(MAP-2)的免疫活性强度。结果:大鼠局部脑缺血再灌注后,运动组前肢放置试验和平衡试验评分优于对照组,前肢放置试验在第9、11、13、15、17、19、21、23、25天差异具有显著性(P均<0.01),平衡试验在第7、9、11、13、17、19天差异具有显著性(P<0.01—0.05)。运动组皮层缺血周边区GAP-43和MAP-2表达水平高于对照组,前者在第7天、14天、28天差异有显著性(P<0.05),后者在第14天、28天差异有显著性(P<0.05)。结论:运动训练能促进大鼠MCAO后的肢体功能恢复,其机制可能与缺血周边区GAP-43和MAP-2的表达上调有关。

Exercise training on functional recovery and the level of expression of GAP-43,MAP-2 after focal cerebral ischemia/reperfusion in rats

Objective:To observe the effect of exercise training on the functional outcome and measure the level of expression of growth-associated protein(GAP-43)and microtubule-associated protein(MAP-2)which are associated with neurite plasticity after focal cerebral ischemia/reperfusion in the rat.Method:After120min of middle cerebral artery occlusion(MCAO)and24hours of reperfusion,the swimming training group rats swam in a pool for10min daily while the control group was without any treatment.Animals were exmined every other day using two different behavioral test to assess sensorimotor function.Brains from the MCAO rats of swimming training,the control,the sham and normal were processed by immunohistochemistry with monoclonal antibodies against GAP-43and MAP-2respectively.Result:There was improvement in the score of behavioral test in swimming training group compared with the control.Immunostaining showed increase in both GAP-43and MAP-2immunoreactivity in ischemic boundary zone in swimming group with a statistic significance(P<0.05).Conclusion:Early swimming training can improve behavioral outcome of MCAO rats.The function enhancement may be partially due to the upregulation of GAP-43and MAP-2which are concomitant with neurite outgrowth.