Objective: To observe the effect of Huoxue capsule on atherosclerotic plaque in rabbits and explore the possible mechanism of stabilizing atherosclerotic plaque. Method: Fifty-three healthy male rabbits were randomly divided into two groups. The rabbits in blank group were fed with common forage. The rabbits in experimental group were fed with high lipid forage. After 10 weeks

rabbits in experimental group were randomly chose to be dissected and atherosclerotic plaque was found and high density lipoprotein-cholesterol(HDL-C) level in the blood was examined to verify whether the model is completed. Then all rabbits in model group were randomly divided into 4 groups:including the model group

the positive control group

and the groups of high and low dose Huoxue capsule

which were fed high lipid forage and blank group fed common forage continuously. Twenty weeks later

blood simples were collected to determine the serum total cholesterol(TC)

triglyceride(TG)

lew density lipoprotein chlesterol(LDL-C) and HDL-C

the thickness ratio of intima and tunica media were measured and the expression intensity of vascular endothelial growth factor(VEGF) and vascular cell adhesion molecule 1(VCAM-1) in the thoracic aorta was determined with immunohistochemical staining. Result: After treatment

the serum levels of TC

TG

LDL-C

and the intima/tunica media thickness ratio significantly reduced(P<0.05). There was a significant difference between the groups of high dose and low doseof Huoxue capsule (P<0.05).Positive expressions of VEGF and VCAM-1 found was in the model group

high-dose and low-dose of Huoxue capsule

and the simvastatin one.The expressions mainly existed in the atherosclerotic plaque

but there was no positive expressions of VEGF and VCAM-1 in the blank group. The results of integral optical density suggested that the expressions in treatment groups were decreased compared with the model group(P<0.01

P<0.05). Conclusion: Huoxue capsule can inhibit the expressions of VEGF and VCAM-1 in the thoracic aorta of the rabbits

and this maybe a mechanism in postponing the process of the atheriosclerosis and stabilizing atheromatous plaque.