Cao SU, Tao XİA, Shen REN, She QİNG, Ding JİNG, Huang LİAN, Qin BİN, Zhou YUAN, Zhu XİANG

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

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

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