依达拉奉对脑缺血再灌注损伤保护作用机制的研究

Neuroprotective mechanism of edaravone on rat brain damage following cerebral ischemia-reperfusion

目的探讨依达拉奉对脑缺血再灌注损伤的保护机制。方法将45只健康雄性W istar大鼠随机分为假手术组、生理盐水对照组、依达拉奉干预组各15只,采用线栓法制作大鼠大脑中动脉缺血模型,脑缺血2h再灌注即刻及12h干预组给予依达拉奉3mg/kg,对照组给予等量生理盐水分别腹腔注射。于24h后断头取脑,免疫组化法测细胞色素C(Cyt C)、半胱氨酸蛋白酶-3(Caspase-3),TUNEL法检测神经细胞凋亡,化学比色法测MDA、SOD,TTC染色测梗死体积。结果假手术组无梗死现象,免疫反应阳性细胞及凋亡细胞亦少见。依达拉奉干预组与生理盐水对照组相比,Cyt C阳性细胞数、Caspase-3阳性细胞数及凋亡细胞数均明显减少,MDA含量减少,SOD活性有所恢复,差异均有统计学意义。生理盐水对照组可见明显大脑中动脉供血区梗死灶,依达拉奉干预组亦可见到梗死灶,与对照组比梗死体积占全脑体积的百分比明显缩小(t=6.576,P<0.01)。结论依达拉奉有自由基清除作用,减少了Cyt C的释放,抑制了细胞凋亡,并缩小了梗死体积;依达拉奉可能通过线粒体途径抑制细胞凋亡,对脑缺血再灌注损伤有保护作用。

Objective To study the neuroprotective mechanism of edaravone on rat brain damage following cerebral ischemia-reperfusion. Methods 45 male Wistar rats were randomly divided into sham-operated groups, physiological saline control groups and edaravone-treatment groups. The temporary middle.cerebral artery occlusion model was applied and reperfused after 2 hours. After the reperfusion immediately and 12 hours, all rats were performed intraperitoneal injection, with edaravone by 3.0mg/kg to the edaravone-treated groups, and with the same volume physiological saline to controls. After 24 hours, rats were decapitated in all the groups. The apoptosis cells were found by TUNEL method and the expression of cytochrome C （Cyt C）and caspase-3 was detected by immunohistochemistry. The infarction volumes were indicated by TTC stain,MDA and SOD were detected by chromatometry 24 hours after reperfusion. Results The infarctions were not observed in sham-operated groups, in which the immunological positive cells and apoptosis cells were hardly found ,while a lot of immunological positive cells of Cyt C, Caspase-3 and apoptosis cells were found in control groups. Compared with the control groups, these cells decreased significantly and MDA content decreased while SOD activity restored in the treatment groups. The infarction volumes of treatment groups were less than those of control groups（ t = 6. 576 ,p 〈 0.01 ）. Conclusion Edaravone could clean up free radicals, decrease the expression of the Cyt C and diminish the neuronal apoptosis and infarction volumes. The neuroprotective mechanism of edaravone maybe lie in inhibiting apoptosis through protecting mitoehondria function.