高密度脂蛋白对缺血再灌注大鼠心肌损伤保护作用的研究

目的 探讨高密度脂蛋白(HDL)预处理对大鼠心肌缺血再灌注的影响.方法 将42只SD大鼠随机分为假手术组(S组)、缺血再灌注组(IR组)和缺血再灌注HDL预处理组(H/IPC).以穿线结扎左冠状动脉制备心肌缺血再罐注模型,H/IR组缺血前10 min经尾静脉注入HDL(30 mg/kg).检测3组大鼠缺血再灌注后30、60、120、240 min血清肌酸激酶(CK)、细胞间黏附分子-1(ICAM-1)的含量;观察3组大鼠缺血再灌注后120 min心肌组织病理学变化.结果 H/IPC组与IR组比较,大鼠CK、ICAM-1含量均降低,下降率分别为36.5%、32.0%、12.6%(P＜0.01);S组CK、ICAM-1含量明显低于IR组(P＜0.01),S组心肌纤维大小均匀、线粒体结构清楚;与IR组比较,H/IPC组伤后240 min心肌细胞变性、炎性细胞浸润及线粒体肿胀程度减轻,且未见细胞溶解坏死.结论 HDL对大鼠心功能的保护作用,可能与HDL抑制ICAM-1的表达有关.

Effects of HDL preconditioning on ischemia-reperfusion myocardial injury in rats

Objective To investigate the effects of HDL preconditioning on ischemia-reperfusion myocardial injury in rats. Methods 42 SD rats were divided randomly into three groups:sham operation group(S),ischemic/reperfusion groups (I/R), HDL/ischemic preconditioning groups (H/IPC), The ischemia-reperfusion heart model was established by ligating and loosening the left anterior descending branch of coronary artery in SD rats. The creatine kinase(CK), expressions of ICAM-1 were detected by ELISA, and morphological changes of myocardial tissues were observed under light microscope and electron microscope. Results The contents of CK,ICAM-1 in the sham operation groups were obviously lower than those in I/R groups (P<0.01) ,while those in HDL-I/R group were also markedly lower than those in sham operation group (P<0.01) .The size and the structure of the cardiac muscular fiber in the sham operation group were even and normal. Compared with those in I/R group,degeneration ,inflammatory infiltration and mitochondrial swelling were found to be less marked in the H/IPC group at 240 min ,and focal lysis and necrosis were not found ,which were found in I/R group. Conclusions High density lipoprotein has the protection effect on heart function of ischemia/reperfusion myocardial injury in rats, the mechanism is probably because high density lipoprotein can inhibit the expressions of ICAM-1 in the myocardial tissues.