Aim To explore the effect of berberine on the angiotensin Ⅱ(AngⅡ) receptor type 1(AT1R) in the prevention of carotid artery atherosclerosis in rabbits.MethodsThirty-two New Zealand white rabbits were divided into four groups: normal group,carotid artery atherosclerosis(model group) group,normal saline group(control group) and berberine prevention group(berberine group).Except normal group with normal diet,other groups were fed with high cholesterol-diet and airdried on the common carotid,on the basis of that,physiological saline group and berberine group were treated with intramuscular physiological saline injection and berberine respectively.After air-dry for four weeks,all rabbits were sacrificed with anaesthesia.The right carotid arteries were also harvested for HE staining and immunohistochemistry of AT1R after the sacrifice.ResultsThe vasculature structure of the carotid arteries was characterized by foam cells which formed atheromatous plapue in model group,and thickening in intima with few foam cells underneath in berberine group.There were few positive cells in media of the common carotid in normal group and the expression of AT1R was found both in model group and control group,and the former was much lower.The number density of the positive cells in berberine group were decreased compared with that in control group(p<0.05).ConclusionsThe mechanism of preventing development of carotid artery atherosclerosis for berberine may be through inhibiting expression of AT1R.