头部亚低温对完全性缺血再灌注后脑保护作用的研究

Study on protective effect of mild hypothermia on brain after complete cerebral lschemia reperfusion

目的 观察头部选择性亚低温对完全性缺血再灌注后的脑保护作用及其对脑组织中超氧化物歧化酶(SOD)和脂质过氧化物(LPO)水平的影响。方法 采用Pittsburgh室颤模型,12只实验犬分为两组:常温对照组和亚低温实验组。运用放射免疫分析法和硫代巴比妥色法分别测定常温组及亚低温组犬脑组织SOD和LPO水平,并行脑组织病理形态学损害评分(HDS)。结果 亚低温组脑组织病理形态学损害较常温组明显改善,HDS较常温组明显降低(P<005);脑组织中SOD明显升高(P<001),而LPO则明显降低(P<001)。结论 头部选择性亚低温对完全性缺血再灌注后的脑具有保护作用,其机制可能是通过缓解缺血再灌注期间氧自由基所介导的脂质过氧化反应及减少SOD消耗而实现的。

Objective To observe the effect of mild hypothermia on the complete cerebral ischemia reperfusion , and the content of superoxide dismutase (SOD) and lipid peroxide (LPO) in canine brain tissue .Methods Using Pittsburgh dog model with ventricular fibrillation cardiac arrest .12 canine were divided into two groups :normothermia and hypothermia group .Radioimmunoassay and thiobarbituric acid method were used respectively to determine SOD and LPO in canine brain tissue .Histopathologic damage scores (HDS)were given for brain tissue Results The HDS in the mild hypothermia group was significantly lower than that in the normothermia group ( P <0.05).The SOD was significantly lower ( P <0 01) ,and the LPO was significantly higher( P <0 01)in the former than that in the latter .Conclusions It is suggested that selective brain mild hypothermia have a protective effect on complete cerebral ischemia reperfusion .The protective mechanism might be related to mitigate the lipid peroxidation induced by oxygen free radical. [