强制性使用运动疗法对大鼠脑缺血后神经可塑性的影响

Effects of constraint- induced- movement therapy on neural plasticity after cerebral ischemia in rats

目的:观察强制性使用运动疗法对大鼠脑梗死区周围皮质的生长相关蛋白-43(GAP-43)、突触素(SYP)表达的影响,探讨其促进脑缺血后神经可塑性的机制。方法:采用自体血栓注入并闭塞大脑中动脉的方法制备局灶脑缺血模型。将90只健康SD大鼠随机分为假手术组(Sham组)、局灶脑缺血模型组(MCAO模型)、强制性运动疗法组(CIMT组)各30只。在局灶脑缺血模型成功后7天,运动疗法组建立强制性使用运动疗法模型。参照Bederson评分标准对各组大鼠进行神经功能缺损评分。采用原位杂交技术检测脑梗死区周围皮质GAP-43及SYP mRNA的表达。采用免疫组化技术检测GAP-43及SYP蛋白表达。结果:与模型组比较,运动疗法组在制模后2、4、8周神经功能缺损评分明显降低,而GAP-43及突触素mRNA及蛋白表达在各时间点均明显高于对照组。结论:强制性使用运动疗法能改善大鼠脑缺血神经功能,其机制可能与运动疗法能够促进梗死灶周围皮质GAP-43及SYP的表达,从而促进脑缺血后的突触发生与重塑有关。

Objective：To investigate the effects of constraint-induced movement therapy （CIMT） on the expressions of growth-associated protein 43（GAP-43） and synaptophysin（SYP） after focal cerebral ischemia in rats. Method：A focal cerebral ischemia model of rat was established by embolizing left middle cerebral artery with autologous blood clots. Ninety healthy Sprague-Dawley rats were randomly divided into 3 groups： sham group, CIMT group,and focal cerebral ischemia（MCAO） group,30 in each group. The CIMT group rats were forced to use their impaired limbs by placing their nonimpaired fore-limbs in casts at the 7th day after MCAO. The behavior scores were evaluated. Expressions of GAP-43, SYPmRNA and protein were detected by means of in situ hybridization histochemistry technique and immunohistochemistry. Result：Compared with MCAO group, the scores of neurological deficit were significantly lower, and the ex- pressions of GAP-43, SYPmRNA and protein were obviously higher in CIMT group. Conclusion：CIMT could improve neurological function of rats after cerebral ischemia.The possible mechanism was closely related to up-regulation of expressions of GAP-43 and SYP, thus to improve neural plasticity.