The expression of angiotensinII in myocardium of high cholesterol-induced atherosclerotic rabbit model and the effects of atorvastatin

Objective:To observe the expression of angiotensinⅡ(AngⅡ)in myocardium of high cholesterol-induced atherosclerotic rabbit model and the effect of atorvastatin.Methods:Twenty-two healthy male New-Zealand white rabbits were divided into three groups randomly:control group(n=6),high cholesterol diet group(n=8),and high cholesterol diet plus atorvastatin(2.5 mg·kg-1·d-1)group(n=8).After feeding for eight weeks,the empty stomach blood preparation through central artery at awake state(fasting diet twelve hours)were collected,centrifugalized(3000rpm,10min)and stored at-20℃,the density of the total cholesterol(TC)and low density lipoprotein(LDL-C)were determined.The morphology of aorta is observed by naked eye.The myocardium was taken to determine the expression of AngⅡ by immunohistochemistry.The results were demonstrated by positive unit(PU).Results:The expression of AngⅡ in high cholesterol diet group was significantly higher than control group[(21.65±4.20)PU vs.(4.58±1.20)PU,P0.05];The expression of AngⅡ in high cholesterol diet plus atorvastatin group was significantly lower than those in high cholesterol diet group[(16.50±1.53)PU vs.(21.65±4.20)PU,P0.05],but also significantly higher than control group [(16.50±1.53)PU vs.(4.58±1.20)PU,P0.05].Conclution:The expression of AngⅡ is significantly higher in cholesterol diet group than in control group.It is explained that myocardium RAAS is at the state of activation in hyperlipidemia.Atorvastatin can significantly cut down the activation of the myocardium RAAS.