摘要
目的探讨氧自由基对肌皮瓣的损伤及机体对自由基的清除过程,以及维生素C等抗氧化剂的作用规律。方法以大白兔为动物模型,形成缺血再灌注肌皮辦,动态测定缺血、再灌注不同时间内超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、丙二醛(MDA)变化及静脉滴注维生素C对其影响。结果缺血再灌注损伤在缺血期已经开始,随着缺血时间的延长而加重,再灌注时损伤进一步加重,超氧阴离子自由基(O_2^-)、羟自由基(·OH)于再灌注后不久即被清除,脂质过氧化物的清除需要较长时间,维生素C对缺血再灌注损伤有一定的保护作用。结论在组织移植中应争取最短的缺血、最快的再灌注,应用药物抗氧化时应于缺血前用药并持续至再灌注后数天。
Objective To explore the mechanism and process of myocutaneous flap injury caused by oxygen-free radicals and the action of vitamin C as a scavenger. Methods We studied the enzymatic concentration of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and malondialdehyde (MDA) in rabbit island myocutaneous flap during ischemia and reperfusion and the influence of vitamine c upon the contents of enzymes. Results The tissue biochemical injury began with ischemia and became worse if ischemia continued. The injury was most serious in early reperfusion phase O_2^- and·OH were then scavenged soon after reperfusion. Both SOD and GSH-Px activity increased with reperfusion, but the significant decrease of MDA took more time. Vitamin C could reduce ischemia reperfusion injury to a certain extent. Conclusion We should strive for shorter ischemic period in tissue transplantation. The oxygen-free radical scavenger should be used before ischemia and be continued for many days after repe- rusion.
基金
中国医学科学院基金资助
