头部亚低温对心脏骤停犬血清及脑脊液中超氧化物歧化酶和脂质过氧化物的影响

目的：探讨头部亚低温对心脏骤停犬超氧化物歧化酶（ＳＯＤ）和脂质过氧化物（ＬＰＯ）的影响，为临床脑复苏过程中开展亚低温治疗提供依据。方法：采用放射免疫分析法和硫代巴比妥酸法分别测定犬心脏骤停前及复苏后常温及头部亚低温情况下血清及脑脊液ＳＯＤ和ＬＰＯ水平。结果：复苏后血清及脑脊液ＳＯＤ水平较心脏骤停前明显降低，而ＬＰＯ水平则明显升高；亚低温组脑脊液中ＳＯＤ水平较常温组高，ＬＰＯ水平则较低，但血清中ＳＯＤ及ＬＰＯ水平无明显差异。结论：氧自由基（ＯＦＲ）在心脏骤停所致的脑缺血缺氧性损害中起重要作用，头部亚低温可通过减少脑组织ＯＦＲ生成而起到保护脑的作用。

Effect of head mild hypothermia on the levels of superoxide dismutase and lipid peroxide in serum and cerebrospinal fluid in canine model of cardiac arrest

Objective:To investigate the effect of head mild hypothermia on superoxide dismutase (SOD) and lipid peroxide (LPO)for obtaining the theoretic basis of using mild hypothermia in cerebral resuscitation.Methods:Radioimmunoassay and thiobarbituric acid method were used respectively to determine SOD and LPO in canine serum and cerebrospinal fluid (CSF) before cardiac arrest and after resuscitation under ordinary temperature and with the head under mild hypothermia. Results:The SOD in serum and CSF after resuscitation was lower than that before cardiac arrest and the LPO was significantly higher than that before cardiac arrest.The SOD in CSF in the mild hypothermia group was higher than that in the ordinary temperature normothermia group,while the LPO in CSF was significantly lower in the former group than that in the latter.However,serum SOD and LPO were not found to be significantly different between the two groups.Conclusions:It is suggested that the oxygen free radicals (OFR) play an important role in ischemicanoxic brain damage due to cardiac arrest and head mild hypothermia may have a protective effect on the brain by reducing the production of OFR in brain tissue.