Phosphorylation of endothelial NOS contributes to simvastatin protection against myocardial no-reflow and infarction in reperfused swine hearts： partially via the PKA signaling pathway  

作　　者：Xiang-dong LI Yue-jin YANG Yong-jian GENG Jing-lin ZHAO Hai-tao ZHANG Yu-tong CHENG Yi-ling WU 

机构地区：[1]Department of Cardiology,State Key Laboratory of Cardiovascular Disease,Fu Wai Hospital,National Center for Cardiovascular Diseases,Chinese Academy of Medical Sciences and Peking Union Medical College,Beijing 100037,China [2]The Center for Cardio-vascular Biology and Atherosclerosis,Department of Internal Medicine,The University of Texas Houston Medical School,Houston,TX 77030,USA [3]Department of Cardiology,Beijing An Zhen Hospital,Capital Medical University,Beijing 100029,China [4]The Integration of Traditional and Western Medical Research Academy of Hebei Province,Shijiazhuang 050035,China

出　　处：《Acta Pharmacologica Sinica》2012年第7期879-887,共9页中国药理学报（英文版）

摘　　要：Aim： The cholesterol-lowering drugs statins could enhance the activities of endothelial nitric oxide synthase （eNOS） and protect myocardium during ischemia and reperfusion. The aim of this study was to examine whether protein kinase A （PKA） was involved in statinmediated eNOS phosphorylation and cardioprotection. Methods： 6-Month-old Chinese minipigs （20-30 kg） underwent a 1.5-h occlusion and 3-h reperfusion of the left anterior descending coronary artery （LAD）. In the sham group, the LAD was encircled by a suture but not occluded. Hemodynamic and cardiac function was monitored using a polygraph. Plasma activity of creatine kinase and the tissue activities of PKA and NOS were measured spectrophotometrically, p-CREB, eNOS and p-eNOS levels were detected using Western blotting. Sizes of the area at risk, the area of no-reflow and the area of necrosis were measured morphologically. Results： Pretreatment of the animals with simvastatin （SIM, 2 mg/kg, po） before reperfusion significantly decreased the plasma activity of creatine kinase, an index of myocardial necrosis, and reduced the no-reflow size （from 50.4%±2.4% to 36.1%±2.1%, P〈0.01） and the infarct size （from 79.0%±2.7% to 64.1%±4.5%, P〈0.01）. SIM significantly increased the activities of PKA and constitutive NOS, and increased Sert33 p-CREB protein, Ser1179 p-eNOS, and Ser635 p-eNOS in ischemic myocardium. Intravenous infusion of the PKA inhibitor H-89 （1 mg.kg^-1.minl） partially abrogated the SlM-induced cardioprotection and eNOS phosphorylation. In contrast, intravenous infusion of the eNOS inhibitor L-NNA （10 mg.kg^-1） completely abrogated the SlM-induced cardioprotection and eNOS phosphorylation during ischemia and reperfusion, but did not affect the activity of PKA. Conclusion： Pretreatment with a single dose of SIM 2.5 h before reperfusion attenuates myocardial no-reflow and infarction through increasing eNOS phosphorylation at Ser^1179 and Ser635 that was partially mediated via the PKA signaling pathwayAim： The cholesterol-lowering drugs statins could enhance the activities of endothelial nitric oxide synthase （eNOS） and protect myocardium during ischemia and reperfusion. The aim of this study was to examine whether protein kinase A （PKA） was involved in statinmediated eNOS phosphorylation and cardioprotection. Methods： 6-Month-old Chinese minipigs （20-30 kg） underwent a 1.5-h occlusion and 3-h reperfusion of the left anterior descending coronary artery （LAD）. In the sham group, the LAD was encircled by a suture but not occluded. Hemodynamic and cardiac function was monitored using a polygraph. Plasma activity of creatine kinase and the tissue activities of PKA and NOS were measured spectrophotometrically, p-CREB, eNOS and p-eNOS levels were detected using Western blotting. Sizes of the area at risk, the area of no-reflow and the area of necrosis were measured morphologically. Results： Pretreatment of the animals with simvastatin （SIM, 2 mg/kg, po） before reperfusion significantly decreased the plasma activity of creatine kinase, an index of myocardial necrosis, and reduced the no-reflow size （from 50.4%±2.4% to 36.1%±2.1%, P〈0.01） and the infarct size （from 79.0%±2.7% to 64.1%±4.5%, P〈0.01）. SIM significantly increased the activities of PKA and constitutive NOS, and increased Sert33 p-CREB protein, Ser1179 p-eNOS, and Ser635 p-eNOS in ischemic myocardium. Intravenous infusion of the PKA inhibitor H-89 （1 mg.kg^-1.minl） partially abrogated the SlM-induced cardioprotection and eNOS phosphorylation. In contrast, intravenous infusion of the eNOS inhibitor L-NNA （10 mg.kg^-1） completely abrogated the SlM-induced cardioprotection and eNOS phosphorylation during ischemia and reperfusion, but did not affect the activity of PKA. Conclusion： Pretreatment with a single dose of SIM 2.5 h before reperfusion attenuates myocardial no-reflow and infarction through increasing eNOS phosphorylation at Ser^1179 and Ser635 that was partially mediated via the PKA signaling pathway

关 键 词：heart ischemia-reperfusion injury NO-REFLOW INFARCTION SIMVASTATIN H-89 L-NNA protein kinase A CREB endothelial NOS 

分 类 号：Q55[生物学—生物化学] Q255