PI3K—Akt—eNOS信号转导通路在七氟醚后处理减轻大鼠心肌缺血再灌注损伤中的作用  

Role of PDK-Akt-eNOS signaling pathway in attenuation of myocardial ischemia-reperfusion injury by sevoflurane postconditioning in rats

作　　者：刘悦[1] 彭云水[2] 刘雅[1] 任建军[1] 刘海涛[1] 韩建民[1] 董振明[1] 

机构地区：[1]河北医科大学第二医院麻醉科,石家庄市050051 [2]河北省医学情报研究所《中华麻醉学杂志》编辑部

出　　处：《中华麻醉学杂志》2012年第3期371-374,共4页Chinese Journal of Anesthesiology

摘　　要：目的评价磷酯酰肌醇-3-激酶／丝氨酸．苏氨酸激酶，内皮型一氧化氮合酶（PI3K-Akt-eNOS）信号转导通路在七氟醚后处理减轻大鼠心肌缺血再灌注损伤中的作用。方法健康雄性Wist—ar大鼠50只，体重250—280g，2—3月龄，采用随机数字表法，将大鼠随机分为5组（n=10）：假手术组（s组）、缺血再灌注组（I／R组）、七氟醚后处理组（Spo组）、七氟醚后处理＋二甲基亚砜组（Spo＋D组）和七氟醚后处理＋P13K特异性抑制剂LY294002组（Spo＋L组）。I／R组、Spo组、Spo＋D组和Spo＋L组采用结扎左冠状动脉前降支30min的方法制备心肌缺血再灌注损伤模型。Spo组、Spo＋D组和Spo＋L组进行七氟醚后处理：再灌注前1min使呼气末七氟醚浓度达到2．5％-3．0％，持续吸入5min；Spo＋L组于再灌注前5min静脉注射LY2940020．3mg／kg，Spo＋D组给予等容量二甲基亚砜。再灌注120min时，每组取10只大鼠，采集动脉血样，检测血清LDH、CK-MB的活性和cTnI浓度。每组处死5只大鼠，取心脏，分离左心室，计算心肌梗死体积；每组处死5只大鼠，取心肌组织，测定Akt、磷酸化Akt（p．Akt）、eNOS和磷酸化eNOS（p-eNOS）的表达，计算p-Akt表达与Akt表达的比值（p-Akt／Akt）和p-eNOS表达与eNOS表达的比值（p-eNOS／eNOS）。结果与s组比较，其余4组血清CK-MB、LDH的活性、cTnI浓度、心肌梗死体积升高，心肌p-Akt／Akt和p-eNOS／eNOS升高（P〈0．05或0．01）；与I／R组比较，Spo组和Spo＋D组血清CK-MB、LDH的活性、cTnI浓度和心肌梗死体积降低，心肌p-Akt／Akt和p-eNOS／eNOS升高（P〈0．05或0．01），Spo＋L组上述指标差异无统计学意义（P〉0．05）；Spo组与Spo＋D组上述指标比较差异无统计学意义（P〉0．05）。结论PDK-Akt—eNOS信号转导通路介导了七氟醚后处理减轻大鼠心肌缺血再灌注损伤作用。Objective To investigate the role of PI3-kinase-Akt-endothelial nitric oxide synthase （PI3K- Akt-eNOS） signaling pathway in the attenuation of myocardial ischemia-reperfusion （I/R） injury by sevoflurane posteonditioning in rats. Methods Fifty healthy male Wistar rats weighing 250-280 g aged 2-3 months were randomly divided into 5 groups （ n = 10 each） ： sham operation group （group S）, I/R group, sevoflurane posteonditioning group （group Spo）, sevoflurane postconditioning ＋ dimethyl sulfoxide （DMSO） group （group Spo ＋ D）, and sevoflurane posteonditioning ＋ LY294002 （a specific PI3K inhibitor） group （group Spo ＋ L）. I/R was produced by occlusion of anterior descending branch of left coronary artery for 30 min followed by 120 min reperfnsion in anesthetized rats. In group Spo, sevoflurane was inhaled for 5 min after the end-tidal concentration reached 2.5%-3.0% at 1 rain before reperfusion. In group Spo ＋ L, LY294002 0.3 mg/kg in 0.02% DMSO was injected intravenously at 5 min before reperfusion, and then sevoflurane postconditioning was performed. In group Spo ＋ D, 0.02% DMSO equal to the volume of LY294002 was injected intravenously at 5 min before reperfusion, and then sevoflurane postconditioning was performed. Arterial blood samples were taken at 120 min of reperfusion for determination of the levels of creatine kinase isoenzyme MB （CK-MB）, lactate dehydrogenase （LDH） and cardiac Troponin I （cTnI） . The myocardial infarct size （IS） and area at risk （AAR） were measured and IS/AAR ratio was calculated. The rats were sacrificed at 120 min of reperfusion and the myocardial tissues in the area at risk were taken for determination of the expression of Akt, phosphorylated Akt （p-Akt）, eNOS and phosphorylated eNOS （p- eNOS） by Western blot. The ratios of p-Akt/Akt and p-eNOS/eNOS were calculated. Results Compared with group S, the levels of CK-MB, LDH and cTnI, IS/AAR ratio, p-Akt/Akt ratio and p-eNOS/eNOS ratio were significantly increased in

关 键 词：1-磷脂酰肌醇3-激酶 蛋白质丝氨酸苏氨酸激酶 一氧化氮合酶Ⅲ型 麻醉药  吸入 心肌再灌注损伤 后处理 

分 类 号：R965[医药卫生—药理学]