鞘内远端吗啡预处理对大鼠心肌缺血后Akt/eNOS信号通路及细胞凋亡的影响  

Effects of intrathecal morphine remote preconditioning on Akt/eNOS signaling pathways and myocardial apoptosis in rats

作　　者：陆姚 胡军 张野 董春山 余骏马 夏良勇 

机构地区：[1]安徽医科大学第三附属医院麻醉科,合肥230061

出　　处：《中华急诊医学杂志》2014年第7期776-780,共5页Chinese Journal of Emergency Medicine

基　　金：国家自然科学基金（81100105）

摘　　要：目的 探讨丝氨酸-苏氨酸激酶（Akt）/内皮型一氧化氮合酶（eNOS）信号通路在鞘内远端吗啡预处理减轻在体大鼠心肌缺血-再灌注损伤和细胞凋亡中的作用.方法 鞘内置管成功的雄性SD大鼠36只,随机（随机数字法）分为3组：假手术组（Sham组）、缺血-再灌注组（I/R组）和鞘内远端吗啡预处理组（RMPC组）.采用缺血30 min再灌注120 min的方法制备心肌缺血-再灌注模型.RMPC组在缺血前30 min内经5 min鞘内输注吗啡l μg/kg（用生理盐水稀释到10 μL）,停止5 min,共3个循环;I/R组给予等容量生理盐水.记录吗啡预处理前（基础值）、缺血前即刻、缺血30 min、再灌注120 min时MAP和HR以及MAP与HR的乘积（RPP）.实验结束处死大鼠,取心肌组织,计算梗死区体积及梗死区面积与缺血危险区体积的比值（IS/AAR）;采用TUNEL染色法检测心肌细胞凋亡,计算凋亡指数（AI）;采用Western blot法测定心肌组织Akt、磷酸化Akt （p-Akt）和eNOS表达.结果 与Sham组比较,I/R组的IS体积、IS/AAR、心肌细胞AI和心肌组织p-Akt表达均增加（P＜0.01）,而心肌组织eNOS表达下调（P＜0.01）;与I/R组比较,RMPC组IS体积、IS/AAR和心肌细胞AI均降低（P＜0.01）,心肌组织p-Akt和eNOS表达上调（P＜0.01）.结论 鞘内远端吗啡预处理减轻在体大鼠心脏缺血后损伤和心肌细胞凋亡,其机制可能与Akt/eNOS信号通路参与介导有关.Objective To investigate the effects of intrathecal morphine remote preconditioning （MRPC） on protein-serine-threonine kinases-endothelial nitric oxide synthase （Akt/eNOS） signaling pathways and cardiac myocyte apoptosis in rats.Methods Male SD rats weighing 280-320 g were used in this study.A needle was inserted through a surgically created hole into the sub-dural space of spinal cord.Thirty-six rats in which intrathecal needle was successfully placed without complication were randomly divided into 3 groups （n =12 in each）.In group Ⅰ sham operation was performed （Sham）.In group Ⅱ myocardial I/R was produced （I/R）.In group Ⅲ morphine was given intrathecally in 3 repeated doses of 1 μg/kg at 5 min intervals before ischemia （MRPC）.Myocardial I/R was produced by occlusion of left anterior descending branch （LAD） of coronary artery for 30 min followed by 120 min reperfusion.The animals were then sacrificed and hearts removed for measurement of area at risk （AAR） and infarct size area （IS）.IS/AAR ratio was calculated.Myocardial apoptosis was detected by TUNEL and apoptotic index （the number of apoptotic myocardial cells/the total number of myocardial cells） was calculated.The levels of Akt,phosphorylated Akt （p-Akt） and eNOS was determined by Western blot.Results The infarct size,myocardial cell apoptotic index and pAkt level were higher and eNOS level was significantly lower in I/R group than those in group Sham （P ＜ 0.01）.MRPC significantly reduced the infarct size and myocardial cell apoptotic index,and pAkt and eNOS level up-regulated in group RMPC compared with group I/R （P ＜ 0.01）.Conclusions Akt/eNOS signaling pathways probably participate in the protective effects of intrathecal morphine remote preconditioning against myocardial I/R injury and myocardial cell apoptosis in rats.

关 键 词：吗啡 鞘内 远端预处理 心肌再灌注损伤 蛋白质丝氨酸-苏氨酸激酶 

分 类 号：R614[医药卫生—麻醉学]