电针调控AQP4、ZO-1的表达对大鼠脑缺血再灌注损伤的影响＊

目的 探讨电针“水沟穴”、“百会穴”是否可以通过调控AQP4、ZO-1的表达从而减轻脑缺血再灌注大鼠血脑屏障损伤。方法 选用健康的雄性SD大鼠随机分为5组：正常对照组（NC）、MCAO模型组（M）、电针组（EA）、AQP4 siRNA组（siRNA）和空载质粒组（EP）。采用改良后的Longa线栓法建立大鼠脑缺血再灌注模型,电针组于模型构建成功后5 min针刺大鼠的“水沟穴”和“百会穴”,并接电针,AQP4 siRNA组和空载质粒组右侧脑室缓慢注入AQP4 siRNA表达质粒和不含AQP4 siRNA的空载质粒。采用神经功能缺损评分观察各组大鼠神经功能缺损程度,CV染色法测定各组大鼠脑半球肿胀率及脑水肿情况,Western blot技术测定各组大鼠AQP4、ZO-1蛋白含量,RT-PCR测定各组大鼠AQP4、ZO-1mRNA含量。结果 与NC组相比较,M组及EP组大鼠神经功能缺损程度及脑水肿程度较重,AQP4蛋白及mRNA表达明显上升,ZO-1蛋白及mRNA表达明显下降;与M组及EP组相比较,EA组及siRNA组大鼠神经功能缺损程度及脑水肿程度较轻,AQP4蛋白及mRNA表达显著下降,ZO-1蛋白及mRNA表达显著上升。结论 电针可以有效抑制AQP4的表达及ZO-1的降低,从而改善血脑屏障的损伤,减少脑水肿的产生,促进神经功能恢复。调控AQP4、ZO-1的表达可能是电针“水沟穴”和“百会穴”改善脑缺血再灌注后脑水肿及血脑屏障损伤的作用机制之一。

Electroacupuncture Alleviates blood-brain barrier disruption by inducing AQP4 and ZO-1 expressions in MCAO Rats

Objective To explore whether electroacupuncture at "Shuigou" (GV26) and "Baihui" (GV20) can alleviate the injury of blood-brain barrier in rats with cerebral ischemia-reperfusion by regulating the expression levels of AQP4 and ZO-1.Methods Healthy male SD rats were randomly divided into 5 groups: normal control group (NC), MCAO model group (M), electroacupuncture group (EA), AQP4 siRNA group (siRNA) and empty plasmid group (EP). The modified Longa thread embolization method was used to make rat cerebral ischemia reperfusion model. In the electroacupuncture group, "shuigou point" and "baihui point" were needled 5min after the model was constructed, and electroacupuncture was received. The siRNA group and the EP group were slowly injected into the right ventricle of AQP4 siRNA and AQP4 siRNA empty plasmid. The neurological deficit score was used to observe the degree of neurological deficit in each group of rats.The CV staining method was used to determine the cerebral hemisphere swelling rate and cerebral edema of each group of rats. The western blot technique was used to determine the protein content of AQP4 and ZO-1 in each group. And the contents of AQP4 and ZO-1mRNA in each group of rats were determined by RT-PCR.Results Compared with the NC group, the neurological deficits and brain edema of the rats in the M group and the EP group were more severe, the expression of AQP4 protein and mRNA increased markedly, while the expression of ZO-1 protein and mRNA decreased markedly. Compared with the M group and the EP group,the degree of neurological deficits and brain edema were lighter, the expression of AQP4 protein and mRNA decreased significantly, while the expression of ZO-1 protein and mRNA increased significantly in the EA group and the siRNA group.Conclusions Electroacupuncture can effectively inhibit the expression of AQP4 and the decrease of ZO-1, thus improving the damage of blood-brain barrier, reducing the generation of cerebral edema and promoting the recovery of neurological function. Regulation of AQP4 and ZO-1 expression may be one of the mechanisms of electroacupuncture at Shuigou and Baihui points to improve cerebral edema and blood-brain barrier injury after cerebral ischemia-reperfusion.