Effect of Diazoxide Preconditioning on Cultured Rat Myocardium Microvascular Endothelial Cells against Apoptosis and Relation of PI3K/Akt Pathway

Abstract

Background:Anti-apoptotic mechanism forcellprotection onre-perfusion may provide a new method to reduce reperfusion injury.Aims:Theaimofthepresent study is toexplore theeffect ofmi-tochondrial ATP sensitive potassium channel (Mito-KATP) opener diazoxide (DZ) preconditioning onhypoxia/ reoxygen (H/R) injury of ratmyocardium microvascular endothelial cells(MMECs) against apoptosis and relation of PI3K/Akt pathway. Study Design: Animal experimentation. Methods:TheratMMECs were cultivated, andH/Rmodel was made to imitate ischemia-reperfusion injury. The cellswereseeds in 96-wellplates (100?L/hole) orin6cmdiameter dishes (2mL/dish) withthedensity of1×106/mL andrandomly divided into4 groups (n=6 each): control group (Group N),hypoxia-regoxygen group (Group H/R), Diazoxide preconditioning+H/R group (Group DZ) andDiazoxide preconditioning +mitochondrial KATP blocker 5-hy-droxydecanoate (5-HD) + H/Rgroup (Group DZ+5-HD). Thecells wereexposed to 2hhypoxia followed by2hreoxygenation. Diazox-ide100?mol/L anddiazoxide 100?mol/L+ 5-HD100?mol/L were added totheculture medium 2hbefore hypoxia inDZandDZ+5-HDgroups respectively. Each group wasobserved theproliferation inMTT, apoptotic ratein Annexin V-FITC/PI double standard, cell structure ofHoechst staining, andthelevels ofPI3K, Aktandp53 mRNA by RT-qPCR. Results:Compared withGroup N,apoptotic rateofGroup H/Rin-creased (p