电针对局灶脑缺血/再灌注大鼠海马内NF-κB旁路途经的调节作用

The effect of Electroacupuncture regulating the NF-κBalternative pathway in the hippocampus of the model rats after focal cerebral ischemia/reperfusion

目的:观察局灶脑缺血/再灌注后不同阶段大鼠海马内IKKα及NF-κBp52的表达及电针对NF-κB旁路途径的调节作用。方法:SD健康雄性大鼠(280-300g)108只随机分为假手术组(n=12),电针组(n=48)及模型组(n=48),按照再灌注后24h与7d将电针组及模型组分为2个亚组。采用右侧大脑中动脉闭塞/再通线栓法建立局灶脑缺血/再灌注模型。电针组取"合谷"穴、"太冲"穴,选用G6805-1型针灸治疗仪进行电针治疗。用FJB染色观察脑缺血/再灌注后海马区内神经细胞的损伤情况;利用免疫组化、Western blot检测不同时间点海马区内IKKα的蛋白表达及NF-κB p52胞核内的蛋白表达变化。结果:FJB染色显示局灶脑缺血/再灌注后,海马区内神经细胞变性损伤明显(P<0.05);与模型组比较,电针干预后海马区内神经细胞变性损伤减少(P<0.05)。免疫组化及Western blot显示模型组大鼠海马内IKKα表达于再灌注后24h及7d均显著升高(P<0.05);胞核内NF-κB p52的蛋白表达随IKKα表达增加而增加(P<0.05)。电针组与模型组比较,海马内IKKα蛋白表达及胞核内p52的蛋白表达明显减少(P<0.05)。结论:脑缺血/再灌注刺激能诱发海马区内IKKα表达升高,活化p52入核激活信号通路造成海马区内神经细胞的损害;电针干预后能明显抑制IKKα的表达,阻止其活化p52进而有效缓解缺血/再灌注后海马内神经细胞的损伤。

Objective ：To observe the effect of electroacupuncture （EA） on the IKKαexpression in the hippocampus at the different time points after ischemia /reperfusion .Methods ：One hundred and eight healthy male SD rats were randomly divided into sham group ,I/R group and EA group .The I/R group and EA group were further divided respectively into 2 subgroups according to the different duration of reperfusion as 24h and 7d .The focal cerebral ischemia/reperfusion was established by middle cerebral artery occlusion/reperfusion . The G6805 -1 electroacupuncture treatment equipment was used and picked the “Hegu” and“Taichong” acupoints in this research .The degeneration of neuron cells was tested by FJB stain .The IKKαprotein expression and the NF -κB p52 expression in the nucleus were detected by immunohistochemistry and Western blot analysis in the hippocampus at different time points .Results Compared with the sham group , the degeneration of neuron cells in the hippocampus in I/R group was significantly increased （P〈0 .05） ,but after the EA treatment ,the neuron cells damage in hippocampus was significantly decreased than that in I/R group （P〈0 .05） .The expression of IKKαprotein in I/R group was remarkably increased at 24h and 7d after reperfusion （P〈0 .05） .Meanwhile ,the NF-κB p52 protein expression in the nucleus was also significantly increased （P〈0 .05） .With EA treatment ,the expression of IKKαand the expression of NF -κB p52 protein expression in the nucleus were significantly decreased （p〈0 .05） .Conclusion The IKKα protein expression was increased by focal cerebral ischemia/reperfusion stimulation ,then activated the NF -κB p52 translocation to activate the signaling pathway and caused the neuron cells damage in the hippocampus after focal cerebral ischemia /reperfusion .The EA treatment significantly inhibited the IKKαexpression ,then stopped the activation of p52 to effectively alleviate the injury in the hippocampus after focal cerebral ischemia /reperfusion .