Abstract： [OBJECTIVE]:To observe the effects of different doses of Wenxiao Ⅱ Decoction on the expression of monocyte chemoattractant protein-1 (MCP-1) and vascular cell adhesion molecule-1 (VCAM-1) in an experimental model of atherosclerosis in rabbits and to explore the mechanism by which it alleviates atherosclerosis.[METHODS]:Sixty 3-4 month-old New Zealand rabbits of both sexes were randomly divided into six groups:simvastain;model;blank;and high-dose,mid-dose,and low-dose Wenxiao Ⅱ Decoction groups.Except for those in the blank group,all rabbits were fed a high-cholesterol diet.Carotid atherosclerosis was established by balloon-induced injury to the endothelium of the carotid artery in conjunction with consumption of a high-cholesterol diet.After 8 weeks,all rabbits were killed to evaluate the expression of MCP-I and VCAM-I by immunohistochemical staining.[RESULTS]:Expressions of MCP-1 and VCAM-1 were significantly decreased in all groups except the blank group compared with the model group (P＜0.05).When compared with the simvastain group only variation of MCP-1 expression in low-dose group was not appreciable,and the differences were indistinct (P＜0.05).When comparing among Wenxiao Ⅱ Decoction groups,MCP-1 expression in the mid- and high-dose groups was significantly lower than that seen in the low-dose group (P＜0.01),but there were no differences among three dosage groups with respect to VCAM-1 expression (P＞0.05).[CONCLUSION]:These data suggested that high,mid,and low doses of Wenxiao Ⅱ Decoction can inhibit the expression of MCP-1 and VCAM-1,which may prevent the formation of or stabilize atherosclerotic plaques.There may be a direct relationship between the dosage of Wenxiao Ⅱ Decoction and its therapeutic efficacy.