脑缺血再灌流过程中沙土鼠脑组织和血浆SOD、MDA含量的变

复制沙土鼠实验性脑缺血再灌流模型，测定了在缺血及再灌流不同阶段血清及脑组织中超氧化物歧化酶（ＳＯＤ）的活性和脂质过氧化反应最终产物（ＭＤＡ）的含量变化，结果发现单纯缺血组与再灌流各组脑组织ＭＤＡ的含量均高于正常对照组，且再灌流１ｈ、６ｈ组的ＭＤＡ含量明显高于单纯缺血组（Ｐ＜０．０５），并有随再灌时间延长不断升高的趋势，但三个再灌流组之间比较无明显差异。单纯缺血组与再灌流各组比较脑组织ＳＯＤ的活性均较正常对照组降低，以再灌１ｈ、６ｈ最为明显，与单纯缺血组比较Ｐ＜０．０５。实验各组与正常对照组比较血浆ＳＯＤ的活性无显著差异。表明单纯缺血和再灌流后均发生了脂质过氧化反应，并认为自由基引起的损伤，在缺血后再灌流中比单纯缺血更为严重。

Changes of SOD and MDA Concentration in Gerbil Brain Tissue and Plasma During Cerebral Ischemia and Reperfusion

Mongolian gerbils were divided into six groups: normal group; ischemia groups with common carotid ligation for 15 and 30 min; reperfusion groups with relax the ligated artery for 30 min, 1 and 6 h after 30 min ischemia. The contents of SOD and MDA in brain tissue and plasma were measured. Results showed that the MDA contens of the ischeimia groups and reperfusion groups in the tissue and plasma all increased significantly and their levels were significant higher with time dependent in groups of reperfusion than that of ischemia groups( P < 0.05 ). At the same time, it was found that thd SOD activity decreased in tissue and the values were much lower in reperfusion groups than that of ischemia groups( P < 0.05 ). However the serum SOD in the all experimental groups was not different from that of normal group. It suggests that the lipid peroxidation took place in the ischemic and reperfused cerebrum. The free radicals may play important role in tissue injury during ischemia reperfusion process, especially in the reperfusion stage.