大鼠局灶性脑缺血再灌注后脑组织的氧化损伤

Oxidative damage to brain tissue of rats after focal cerebral ischemic/reperfusion injury

目的:通过观察大鼠局灶性脑缺血再灌注后脑组织超氧化物歧化酶活性和丙二醛含量的变化,进一步探讨大鼠局灶性脑缺血再灌注后氧化损伤的病理生理改变。方法:实验于2004-09/2005-01在泸州医学院神经生物学教研室进行。将雄性成年Wistar大鼠60只随机分为2组:假手术组30只和缺血再灌注组30只。每组分3个观察时间点,分别为手术后6,12,24h,每个时间点10只。采用线栓法制成大脑中动脉闭塞模型,假手术组手术过程同缺血再灌注组,但未插栓线,不造成脑缺血。测定手术后不同时点脑组织超氧化物歧化酶活性和丙二醛水平。结果:在实验过程中有6只大鼠死亡,缺血再灌注组有8只大鼠手术后模型评价为0级,被排除实验,随机补充14只大鼠,最终进入结果分析仍为60只大鼠。①缺血再灌注组术后6,12,24h超氧化物歧化酶活性均低于假手术组眼(289.72±10.67),(534.77±22.67)μkat/L;(330.57±18.17),(539.11±11.50)μkat/L;(377.58±14.67),(550.78±11.50)μkat/L,P<0.05演。②缺血再灌注组术后6,12,24h丙二醛水平显著高于假手术组眼(15.06±0.59),(6.78±0.25)μmol/L;(13.53±1.11),(6.78±0.26)μmol/L;(11.31±0.97),(6.80±0.26)μmol/L,P<0.05演。结论:脑缺血再灌注后,缺血大鼠脑组织内丙二醛水平升高,超氧化物歧化酶活性降低,说明自由基参与了脑缺血再灌注损伤的病理生理过程。

AIM： To explore further the pathological and physical changes of oxidative damage on experimental cerebral ischemia-reperfusion injury of rats by observing the changes of activity of superoxide dismutase and level of malondialdehyde on brain tissue after focal cerebral ischemic/reperfusion injury of rats. METHODS： The experiment was conducted at the Staff Room of Neurobiology, Luzhou Medical College between September 2004 and January 2005. Sixty male adult Wistar rats were randomly divided into 2 groups： Sham operation group with 30 rats and ischemic/reperfusion group with 30 rats. There were 3 observational time points in every group： 6, 12 and 24 hours after operation with 10 rats in each time point. Models with occlusion of middle cerebral artery were made with thread occlusion method. The procedure of operation in the sham operation group was the same to the ischemic/reperfusion group, but without occlusion. Activity of superoxide dismutase （SOD） and level of malondialdehyde （MDA） in the different time point after operation. RESULTS： Six rats died in the process of experiment. Evaluation in the eight rats of the ischemic/reperfusion group was 0 level after operation, and were excluded, and then 14 rats were complemented randomly. A total of 60 rats were involved in the result analysis. ①Activities of SOD at 6, 12 and 24 hours in the ischemic/reperfusion group were lower than those in the sham operation group [（289.72 ±10.67）, （534.77±22.67）μkat/L; （33057±18.17）, （539.11±11.50）μkat/L; （377.58±14.67）, （550.78±11.50）μkat/L, P〈 0.05]. ②Levels of MDA at 6, 12 and 24 hours in the isehemie/reperfusion group were higher significantly than those in the sham operation group [（15.06±0.59）, （6.78±0.25）μmol/L; （13.53±1.11）, （6.78±0.26）μmol/L; （ 11.31±0.97 ）, （6.80±0.26） μmol/L, P 〈 0.05]. CONCLUSION： The levels of MDA of rats in isehemie/repeffusion group increased, and the activities of SOD decreased. It showed that free radicals attended the pathological and physical functions of cerebral isehemic/reperfusion injury.