限制性再灌注对脑缺血再灌注损伤的保护作用

Protective effect of restrictive reperfusion against cerebral ischemia-reperfusion injury

目的探究限制性再灌注对小鼠大脑中动脉闭塞(MCAO)模型缺血再灌注损伤的保护作用。方法采用雄性C57BL/6J小鼠进行实验观察,其中假手术组7只,左颈总动脉结扎组(LCO组)10只,通常再灌注组(ecMCAO组)17只,限制性再灌注组(ccMCAO组)22只。LCO组小鼠进行左侧颈总动脉结扎手术,24 h后行神经损伤评分和组织学评估。ecMCAO组小鼠经颈外动脉线栓造模,ccMCAO小鼠经颈总动脉线栓造模,在MCAO造模后2 h再灌注。小鼠在麻醉苏醒即刻与再灌注24 h,分别进行神经损伤评分,然后取材评估组织损伤。干湿重法测量脑组织含水量,并判断是否存在颅内出血。结果LCO组小鼠各项指标与假手术组无明显差异。ecMCAO组小鼠再灌注24 h后神经损伤评分显著高于ccMCAO组(P<0.05)。ecMCAO组小鼠脑组织损伤体积与脑组织含水量大于ccMCAO组(均P<0.05)。脑出血率趋势ecMCAO组小鼠高于ccMCAO组,但无统计学意义。结论C57 BL6/J小鼠大脑对侧代偿功能较好。与ecMCAO相比,ccMCAO模型再灌注后引起的组织与功能损伤较轻,说明限制性再灌注对小鼠脑缺血再灌注损伤有保护作用。

Objective To investigate the protective effect of restrictive reperfusion from ischemia-reperfusion injury in mouse middle cerebral artery occlusion(MCAO)model.Methods Male C57 BL/6 J mice were used for experimental observation,including 7 in sham group,10 in the LCO group,17 in the ecMCAO group and 22 in the ccMCAO group.Mice in the LCO group underwent left carotid artery occlusion.Neurological deficit score(NDS)and histological evaluation were performed 24 h after occlusion.Mice in the ecMCAO group were modeled with external carotid arterial occlusion and ccMCAO mice were modeled with common carotid arterial occlusion,and reperfused 2 h after MCAO modeling.Immediately after waking up from anesthesia and 24 hours after reperfusion,the mice were scored for NDS,and then the tissue damage was assessed.Dry-wet weight ratio of brains was measured and the rates of intracranial hemorrhage were recorded.Results There were no significant differences in all indexes between the LCO group and the sham group.The NDS of ecMCAO group was significantly higher than that of ccMCAO group after 24 h reperfusion(P<0.05).The volume of brain tissue damage and the moisture content in the ecMCAO group was larger than that in the ccMCAO group(both P<0.05),and the rate of intracranial hemorrhage was higher in ecMCAO group than in the ccMCAO group,but it was not statistically significant.Conclusions The compensatory ability of the contralateral carotid artery system is fine in C57 BL6/J mice.Compared with ecMCAO,the ccMCAO model would cause less tissue and functional damage after reperfusion,indicating that restrictive reperfusion has protective effects against cerebral ischemia-reperfusion injury in mice.