舒芬太尼对大鼠心肌缺血再灌注时自噬的影响

Effect of sufentanii on autophagy during myocardial ischemia-reperfusion in rats

目的评价舒芬太尼对大鼠心肌缺血再灌注时自噬的影响。方法成年雄性SD大鼠18只，体重200—250g，采用随机数字表法分为3组（n=6）：假手术组（SH组）、心肌缺血再灌注组（I／R组）和舒芬太尼组（S组）。I／R组和S组采用结扎左冠状动脉前降支30min，再灌注120min的方法制备大鼠心肌缺血再灌注损伤模型；SH组只穿线，不结扎。S组于缺血前30min时经尾静脉注射舒芬太尼3μg／kg；SH组和I／R组尾静脉注射等容量生理盐水。于再灌注120min时，采集动脉血样，测定血清CK-MB和LDH的浓度，取心肌组织，透射电镜下观察心肌细胞超微结构，采用Western blot法测定自噬蛋白微管相关蛋白1轻链3Ⅱ型（LC3lI）、Beclin-1和Bcl-2的表达。结果与SH组比较，I／R组血清CK-MB和LDH的浓度升高，心肌组织LC3Ⅱ和Beclin-1的表达上调，Bcl-2表达下调，S组血清CK—MB浓度升高，心肌组织Beclin-1和Bcl-2的表达下调（P〈0．05）；与I／R组比较，S组血清CK—MB浓度降低，心肌组织LC3Ⅱ和Beclin-1的表达下调，Bcl-2表达上调（P〈O．05），血清LDH浓度差异无统计学意义（P〉0．05），病理学损伤减轻。结论舒芬太尼减轻大鼠心肌缺血再灌注损伤的机制可能与降低自噬水平有关。

Objective To evaluate the effect of sufentanil on autophagy during myocardial isehemia-reperfusion （I/R） in rats. Methods Eighteen adult male Sprague-Dawley rats, weighing 200- 250 g, were randomly divided into 3 groups （n = 6 each） using a random number table： sham operation group （group SH） , I/R group, and sufentanil group （group S）. Myocardial I/R injury was produced by occlusion of the anterior descending branch of the left coronary artery for 30 min followed by 120 min reperfusion in the rats anesthetized with chloral hydrate in I/R and S groups. Sufentanil 3 μg/kg was injected via the caudal vein at 30 rain prior to ischemia in group S. The equal volume of normal saline was given in SH and I/R groups. At 120 min of reperfusion, arterial blood samples were collected for determination of serum creatine kinase-MB （CK-MB） and lactic dehydrogenase （LDH） concentrations, and myocardial specimens were obtained for examination of the uhrastrueture of myocardial cells （ using transmission electron microscopy） and for determination of autophagy-related proteins microtubule-associated protein 1 light chain 3 H （LC3 1/ ） , Beelin-1 and Bcl-2 expression （by Western blot）. Results Compared with group SH, the serum CK-MB and LDH concentrations were significantly increased, the expression of LC3 Ⅱ and Beelin-1 was significantly up-regulated, and Bcl-2 expression was significantly down-regulated in group I/R, and the serum CK-MB concentration was significantly increased, the expression of Beelin-1and Bcl-2 was significantly down-regulated in group S （P〈0.05）. Compared with group I/R, the serum CK-MB concentrations were significantly decreased, the expression of LC3 Ⅱ and Beclin-1 was significantly down-regulated, Bcl-2 expression was significantly up-regulated （P 〈 0.05）, no significant change was found in serum LDH concentrations （P〉0.05）, and the pathological changes were reduced in group S. Conclusion The mechanism by which sufentanil reduces myocardial I/R injury may be related to decreased autophagy in rats.