RESUMO
Aim To invesitgate the effect of PTEN(phosphatase and tensin homologue deleted on chromo-some ten) /PI3K(phosphatidylinositol 3 kinase) signaltransduction pathway in hypertrophied myocardium me-diated by overloaded pressure in rats,and the effect ofangiotensionⅡ(AngⅡ) receptors(AT1,AT2) antag-onists on it.Methods Overloaded pressure hypertro-phied myocardiumratmodel was established by abdom-inal arota constriction.Thirty two male wistar rats weredivided randomly into four groups,namely sham-opera-ted group,banding group,valsartan group(bandinggroup and valsartan administation),and PD123319group(banding group and PD123319 administration).AngⅡconcentration in plasma and left ventricular myo-cardium were measured by radioimmunoassays.Cardiacindex was measured and HE staining was performedwith left ventricular myocardium,immunoprecitipationwas used to assay the protein expression and phospho-rylation of PTEN、PI3K and Akt(Protein kinase B),protein expression of?-skeletal-actin in myocardial tis-sues.Results AngⅡ concentration in serum and leftventricular myocardium tissue in banding group washigher than that in sham-operated group,valsartangroup andPD123319 group(P0.05).Conclusions PTEN/PI3Ksignal pathway is involved in myocardium hyper-trophy in overloaded pressure rat model.The up-regu-lations of PI3K/Akt and down regulation of PTEN aremediated via AT1 and can be reduced by AT1 receptorantagonists.