摘要
本实验以异丙肾上腺素性心肌缺血为模型,对心肌膜脂、膜酶和自由基系统进行了研究。实验采用SD大鼠,皮下注射异丙肾上腺素85mg/kg,24小时后将动物处死。与正常对照组比较,心肌游离脂肪酸明显增加(P<0.05),线粒体胆固醇/磷脂比值和膜脂流动性升高(P值分别小于0.05和0.001);心肌脂质过氧化产物丙二醛含量增加(P<0.05).且心肌及线粒体的超氯化物歧化酶和谷胱甘肽过氯化物酶活力均升高(P值分别小于0.01和0.05);心肌线粒体Ca^(2+)—Mg^(2+)—ATP酶活力增加,Na^+—K^+—ATP酶活力降低。但5′-核苷酸酶无明显变化。结果提示:ISP—MI大鼠心肌膜脂、膜酶及自由基代谢发生紊乱,提示心肌缺血时膜受损。
The changes in lipids,enzymes and tree-radical system of myocardial cell membranes in rats with experimental myocardial ischemia were investigated in this study. Model myocardial ischemia were perpared by given Sprague-Dawley rats each with 85mg/kg isoproterenol(ISP) hypodermically. All rats were presecuted 24hrs after ISP injection. Study of ischemic hearts demonstrated significant changes, which were increased cholesterol/phospholipid ratio and free fatty acid(FFA) contents,increased mitochondrial membrane fluidity and decreased protein contents. The lipid peroxidation products,malonyldialdehyde(MDA) in ischemic heart increased significantiy,accompanied by increased activity in Ca^(2+)—Mg^(2+)—ATPase activity and decreased in Na^+—K^+— ATPase activity. 5-nucleotidase remained unchanged in ISP-induced myocardial infarction, as compared with normal control. Results of this study suggested that membrane injury was persent during ischemic myocardium as indicated by disturbance in the metabolism of lipids,enzymes and free-radical system.
关键词
膜损伤
心肌缺血
异丙肾上腺素
Membrane injury
Isopropterenol
Myocardial ischemia
Oxysen free radicals
