摘要目的 探讨电针对脑缺血再灌注大鼠学习记忆障碍的改善作用及其机制.方法 简单随机抽样将90只用于跳台实验的SD大鼠随机分为正常对照组、单纯脑缺血再灌注7d、14d、30 d、60 d组(I/R)和脑缺血再灌注7d、14 d、30 d、60 d+电针干预组(I/R+EA),n=10;70只用于分子生物学实验的SD大鼠随机分为正常对照组、单纯脑缺血再灌注3h、6h、12 h组(I/R)和脑缺血再灌注3h、6h、12 h+电针干预组(VR+EA),n=10.采用线栓法制备大鼠脑缺血再灌注模型(MCAO),取大鼠“百会”和“水沟”穴进行电针,终刺激强度为5 mA,持续时间为30 min.做跳台实验观察大鼠学习记忆的修复状况;Western blot检测大鼠脑组织procaspase-3、procaspase-12、PARP和iCAD蛋白的表达;免疫荧光组织化学方法检测GRP94阳性表达的细胞个数.结果 跳台结果显示电针干预后大鼠学习记忆力得到明显改善,电针7d和14 d组大鼠触电潜伏期分别为[(90.60± 17.01)s、(128.80±8.85)s],与脑缺血再灌注7d和14 d组[(51.20±5.09)s、(105.00±10.39)s]相比明显升高,电针7d和14 d组大鼠单脚跳下错误次数分别为[(3.90±0.99)次、(2.70±0.67)次],与脑缺血再灌注7d和14d组[(9.20±1.61)次、(6.10±0.99)次]相比明显降低,差异有统计学意义(P＜0.01);Western blot结果显示电针干预后procaspase-3、procaspase-12、PARP蛋白前体和iCAD蛋白的表达均上调(P＜0.01);免疫荧光组织化学结果显示电针干预后3h、6h和12h组GRP94蛋白阳性细胞数与相应的I/R组比较明显减少(均P＜0.01).结论 电针干预可有效改善缺血再灌注大鼠的学习记忆能力,这可能与通过阻断内质网应激及炎性因子介导的凋亡通路来减少脑缺血再灌注损伤后的脑细胞凋亡有关.

abstractsObjective To explore the effect and possible mechanism of electroacupuncture on learning and memory impairment in rats with cerebral ischemia reperfusion.Methods 90 SD rats used for stepdown test were divided into normal control group,simple cerebral ischemia reperfusion of 7 d,14 d,30 d,60 d group (I/R) and cerebral ischemia reperfusion of 7 d,14 d,30 d,60 d and electroacupuncture intervention group (I/R+EA),through simple random sampling method (10 rats in each group);70 SD rats used for molecular biology experiments were randomly divided into normal control group,simple cerebral ischemia and reperfusion of 3 h,6 h,12 h group (I/R) and cerebral ischemia reperfusion of 3 h,6 h,12 h and electroacupuncture intervention group (I/R+EA),n=10.Use suture method to make model of cerebral ischemia reperfusion in rats.Take the rats' "baihui" acupoint and "shuigou" acupoint to acupuncture.The final strength was 5 mA and the duration was 30 minutes.Step down test was used to observe the restoration of learning and memory in rats.Western blot was used to detect the expression of procaspase-3,procaspase-12,PARP and ICAD in rat cerebral cortex and striatum.Immunofluorescence histochemical method was used to detect the number of GRP94 positive cells.Results The results of the platform showed that the learning and memory abilities of the rats were obviously improved after electroacupuncture treatment.Electric shock incubation period of rats in electroacupuncture of 7 d and 14 d group was (90.60± 17.01) and (128.80±8.85) respectively.It was significantly higher than that of cerebral ischemia reperfusion of 7 d group(51.20±5.09) and 14 d group(105.00± 10.39).The number of mistakes in single foot jump of rats in electroacupuncture of 7 d and 14 d group was (3.90±0.99) and (2.70±0.67) respectively.It was significantly lower than that of 7 d group (9.20± 1.61) and 14 d group (6.10± 0.99).Through SPSS13.0 statistical software one-way ANOVA,the difference was statistically significant (P＜ 0.05).Western blot results showed that the expression of procaspase-3,procaspase-12,PARP protein precursor and ICAD protein,upregulation increased after electroacupuncture(P＜0.05).The results of immunofluorescence histochemistry showed that the number of positive cells of GRP94 protein was significantly decreased after 3 h,6 h and 12 h after electroacupuncture intervention compared with the corresponding I/R group.Conclusion Electroacupuncture can effectively improve the learning and memory ability of rats with ischemia-reperfusion,which may be related to the apoptosis of cerebral cells after cerebral ischemia reperfusion injury by blocking the apoptosis pathway mediated by endoplasmic reticulum and inflammatory factors.