丹皮酚预处理对大鼠脑缺血再灌注损伤的保护作用

The protective effect of paeonol pretreatment on cerebral ischemia reperfusion injury in rats

目的探讨丹皮酚预处理对大鼠脑缺血再灌注损伤的保护作用。方法60只健康雄性SD大鼠随机分为丹皮酚预处理组、模型组、假手术组,每组20只。采用颈外动脉线栓法制作脑缺血再灌注损伤模型,造模前12 h,药物预处理组给予丹皮酚(100 mg·L^(-1)),模型组和假手术组给予等量生理盐水,均采用腹腔注射。造模成功后,采用Zealongal法对大鼠神经功能缺损评分;采用氯化三苯四氮唑(TTC)法判断梗死灶体积;采用原位细胞凋亡检测(TUNEL)法检测海马细胞凋亡;采用免疫组织化学法检测海马细胞Hsp-70、Bcl-2及Bax蛋白表达。结果脑缺血再灌注损伤后,大鼠出现神经功能缺损、梗死灶和Hsp-70、Bcl-2、Bax蛋白表达变化等表现。与模型组比较,丹皮酚预处理组大鼠脑梗死灶缩小、神经功能缺损有所改善,原位细胞凋亡检测和Bax的阳性细胞数明显减少,Hsp-70和Bcl-2的阳性细胞数明显增加(P<0.05)。结论丹皮酚可能通过下调Bax蛋白表达,上调Hsp-70和Bcl-2蛋白表达,减轻脑缺血再灌注损伤后的神经细胞凋亡,对受损神经细胞起到一定的保护作用。

Objective To investigate the protective effect of paeonol pretreatment on cerebral ischemia reperfusion injury in rats.Methods 60 healthy SD rats were randomly divided into the paeonol pretreatment group,model group and sham-operated group,20 rats in each group.The rat cerebral ischemia-reperfusion injury model was constructed by external carotid artery thread-tie method.Before 12 hours of modeling,the drug pretreatment group was given paeonol preparation(100 mg·L^(-1)),the model group and the sham-operated were given same saline,by intraperitoneal injection.After successful modeling,the neurological deficit of rats was evaluated by Zealongal method;the cerebral infarction volume was measured by TTC staining method;the cell apoptosis was measured by TUNEL method;the protein expression of Hsp-70,Bcl-2 and Bax was detected by Immunohistochemistry.Results After cerebral ischemia-reperfusion injury,the rats exhibited neurological deficits,cerebral infarction and the protein expression of Hsp-70,Bcl-2 and bax changed.Compared with the model group,the paeonol pretreatment group rats infarct reduced,neurological deficits were improvement,the number of positive cells of TUNEL and Bax decreased significantly,the number of positive cells of Hsp-70 and Bcl-2 increased significantly(P<0.05).Conclusion Paeonol may down-regulate the protein expression of Bax,up-regulate the protein expression of Hsp-70 and Bcl-2,alleviate the neuronal apoptosis after cerebral ischemia-reperfusion injury,and play a protective role on damaged nerve cells.