摘要
目的 探讨缺血后处理激活大鼠心肌缺血再灌注时NF-E2相关因子2（Nrf2）-抗氧化反应元件（ARE）信号通路的机制与活性氧（ROS）的关系.方法 健康雄性SD大鼠,体重250～300g,16～20周龄,采用Langendorff灌注装置建立大鼠离体心脏灌注模型.取模型制备成功的心脏32个,采用随机数字表法分为4组（n=8）：对照组（C组）、缺血再灌注组（I/R组）、缺血后处理组（IPO组）和ROS清除剂N-（2-巯基丙酰）-甘氨酸＋缺血后处理组（M＋IPO组）.平衡灌注20 min后,C组继续灌注100 min;I/R组灌注4℃St.Thomas停跳液停跳,并在32℃下缺血40 min,再灌注60 min;IPO组于再灌注即刻行缺血后处理,再灌注10 s,缺血10 s,共6个循环,然后恢复灌注58 min;M＋IPO组于再灌注即刻灌注含N-（2-巯基丙酰）-甘氨酸2 mmol/L的K-H液3 min,然后行缺血后处理2min,再灌注55 min.分别于平衡灌注末及再灌注末记录HR、左心室发展压（LVDP）、左心室舒张末压（LVEDP）和左心室压力最大上升速度（＋dp/dtmax）.分别于再灌注5 min和再灌注末时,取左心室心肌组织,采用ELISA法测定ROS含量.于再灌注末,取左心室心肌组织,观察心肌细胞超微结构,并进行线粒体损伤评分,分别采用Western blot法和RT-PCR法检测心肌组织Nrf2、血红素加氧酶-1（HO-1）、醌氧化还原酶1（NQO1）、超氧化物歧化酶1（SOD1）及其mRNA的表达水平.结果 与C组比较,再灌注末I/R组和M＋IPO组HR、＋dp/dtmax和LVDP降低,LVEDP升高,IPO组HR、LVDP降低,LVEDP升高（P＜0.05）,HR和＋dp/dtmax差异无统计学意义（P＞0.05）,I/R组、IPO组和M＋IPO组线粒体损伤评分升高,再灌注末I/R组、IPO组和M＋IPO组ROS含量升高,心肌组织Nrf2、HO-1、NQO1和SOD1及其mRNA表达下调（P＜0.05）.与I/R组比较,IPO组和M＋IPO组再灌注末HR、＋dp/dtmax和LVDP升高,LVEDP和心肌组织ROS含量降低,心肌组织Nrf2、HO-1、NQO1和SOD1及其mRNA表达上调,IPO组线粒
Objective To investigate the relationship between the mechanism of ischemic postconditioning-induced activation of nuclear factor-E2 related factor 2 （Nrf2）-antioxidant response element （ARE） signaling pathway during myocardial ischemia-reperfusion （I/R） and reactive oxygen species （ROS）.Methods Healthy male Sprague-Dawley rats, aged 16-20 weeks, weighing 250-300 g, were heparinized and anesthetized with intraperitoneal 1% pentobarbital sodium 40 mg/kg.Their hearts were excised and perfused in a Langendorff apparatus with K-H solution.Thirty-two isolated rat hearts were randomly divided into 4 groups （n=8 each） using a random number table： control group （group C） , group I/R,ischemic postconditioning group （group IPO） , and N-（2-mercaptopropionyl）-glycine （a ROS scavenger） ＋ IPO group （group M ＋ IPO）.After 20 min of equilibration, group C was continuously perfused with K-H solution for 100 min, and the isolated hearts received the drugs via the perfusion system in the other groups.Group I/R was perfused with cardioplegic solution 4 ℃ St.Thomas, and then was subjected to 40 min of ischemia at 32 ℃ followed by 60 min of reperfusion.In group IPO, ischemic postconditioning was induced by 6 cycles of 10 s reperfusion followed by 10 s limb ischemia starting from the onset of reperfusion, and the hearts were then perfused for 58 min.In group M ＋ IPO, the hearts were perfused with K-H solution containing N-（2-mercaptopropionyl）-glycine 2 m mol/L for 3 min starting from the onset of reperfusion,underwent 2 min of ischemic postconditioning, and then was perfused for 55 min.Heart rate （HR）, left ventricular developed pressure （LVDP）, left ventricular end-diastolic pressure （LVEDP）,and positive maximal pressure of left ventricular increase （＋dp/dtmax） were recorded at the end of equilibration and of reperfusion.At 5 min of reperfusion and the end of reperfusion, myocardial specimens were obtained from the left ventricle for determination of ROS content
出处
《中华麻醉学杂志》
CAS
CSCD
北大核心
2015年第8期998-1002,共5页
Chinese Journal of Anesthesiology
基金
国家自然科学基金（30960366）
