简介：ObjectivesToexploretheprotectiveeffectofirbesartan(Irb)undertheinterferencewithangiotensinⅡ(AngⅡ)onABCA1.MethodsElectronmicroscopywasusedtodetectthemorphousoffoamcells.TheexpressionofABCA1mRNAanditsproteinweredeterminedbyRT-PCRandWesternblotting,respectively.Thevarianceofcellularcholesterolcontentwasmeasuredbyzymochemistryvia-fluorospectrophotometer.ResultsApositivefacilitativeeffectofAngⅡontheformationoffoamcellswasobserved.TotalcholesterolwasincreasedsignificantlybyAngⅡ,theexpressionofABCA1wasdown-regulatedobviouslybyAngⅡ;IrbcouldprotectABCA1againstthelesionofAngⅡ;TotalcellularcholesterolcontentwasreducedsignificantlyinIrb+AngⅡgroup;However,considerablealterationaboutthecholesterolcontentandtheexpressionofABCA1werenotobservedinIrbgroupwithoutincubationwithAngⅡ.ConclusionsIrbcouldprotectABCA1againstthelesionofAngⅡ,whichmaycontributetoitsanti-atheroscleroticproperties.