一氧化氮在吗啡后处理抑制大鼠缺血再灌注心肌细胞凋亡中的作用  

Role of nitric oxide in the protective effect of morphine postconditioning against ischemia-reperfusion-induced myocardial apoptosis

作　　者：王志[1] 赵惠娟[2] 车月娟[1] 李玉娟[1] 王飞[1] 彭书岐[1] 

机构地区：[1]中山大学附属第二医院麻醉科,广州市510120 [2]中山大学附属第一医院手术室,广州市510120

出　　处：《中华麻醉学杂志》2009年第7期659-662,共4页Chinese Journal of Anesthesiology

基　　金：基金项目：广东省医学科研基金资助项目（A2008179）

摘　　要：目的探讨一氧化氮在吗啡后处理抑制大鼠缺血再灌注损伤心肌细胞凋亡中的作用。方法清洁级雄性sD大鼠60只，体重280～330g，随机分为4组（n=15）：假手术组（s组）只穿线不结扎；缺血再灌注组（I／R组）结扎左冠状动脉前降支45min，再灌注120min；吗啡后处理组（M组）再灌注前3min至再灌注2min经左颈内静脉注射吗啡1．25mg／kg；L-NAME＋吗啡后处理组（L＋M组）左冠状动脉前降支结扎前20min静脉注射L-NAME10mg／kg。分别于缺血前、缺血20min及再灌注120min时监测心率（HR）和平均动脉压（MAP），并计算HR与收缩压（SP）的乘积（RPP）；于再灌注120min时取心肌，采用TUNEL法检测心肌凋亡细胞，计算心肌细胞凋亡指数（AI），采用Westernblot法检测总内皮型一氧化氮合酶（eNOS）和磷酸化eNOS蛋白的表达水平，计算磷酸化eNOS蛋白表达与总eNOS蛋白表达的比值（p-eNOS／eNOS），硝酸盐还原酶法测定心肌NO含量。结果I／R组、M组及L＋M组间各时点HR、MAP及RPP差异无统计学意义（P〉0．05）；与s组比较，其余各组AI升高，I／R组和L＋M组心肌NO含量降低，，M组升高（P〈0．05）；与I／R组比较，M组AI降低，M组心肌NO含量升高（P〈0．05），L＋M组差异无统计学意义（P〉0．05），M组和L＋M组p-eNOS／eNOS升高（P〈0．05）；与M组比较，L＋M组AI升高，心肌NO含量降低（P〈0．05），p-eNOS／eNOS差异无统计学意义（P〉0．05）。结论吗啡后处理可通过激活eNOS促进NO产生，抑制大鼠缺血再灌注损伤诱发的心肌细胞凋亡。Objective To investigate the role of nitric oxide （NO） in the protective effects of morphine postconditioning against ischemia-reperfusion （I/R）-induced myocardial apoptosis. Methods Sixty pathogen-free SD rats were randomly divided into 4 groups （ n = 15 each） ： group [ sham operation （S） ; group 11 I/R; group m morphine postconditioning （M） and group IV M ＋ L-NAME （non-selective NOS inhibitor）. The animals were anesthetized with intraperitoneal pentobarbital 60 mg/kg, tracheostomized and mechanically ventilated. ECG was monitored. Right carotid artery was cannulated for BP monitoring and left jugular vein was cannulated for drug and fluid administration. Myocardial isehemia was induced by 45 rain occlusion of left anterior descending coronary artery （LAD） followed by 120 min reperfusion. In group S LAD was exposed but not occluded; in group M morphine 1.25 mg/kg was injected iv over 5 min from 3 min before reperfusion to 2 min of reperfusion and in group M ＋ L-NAME L-NAME 10, mg/kg was injected iv at 20 rain before myocardial ischemia. Hemodynamic changes were monitored. The animals were killed at the end of 120 min reperfusion and their hearts removed. Myocardial apoptosis was determined by TUNEL technique. The expression of Akt phosphorylation was assessed by Western blotting. The NO content in myocardium was measured by a chemiluminescence detector. Results A large number of TUNEL positive cells （18.4 ± 1.1 ） % were observed in group I/R. Morphine postconditioning exerted a significant anti-apoptotic effect. The number of TUNEL positive cells was reduced to （10.8 ±1.2） %. The myocardial eNOS phosphorylation expression and NO content were significantly increased in group M as compared with group I/R. The anti-apoptotic effect and increased NO production were significantly reversed by L-NAME. However, pretreatment with L-NAME did not inhibit the phosphorylation of eNOS in group L ＋ M. Conclusion In vivo, morphine postcondifioning can significantly reduce I/R-induce

关 键 词：一氧化氮 吗啡 心肌再灌注损伤 凋亡 

分 类 号：R96[医药卫生—药理学]