Abstract: Objective To compare the stabilizing effects of Tongxinluo and simvastatin on vulnerable plaques in rabbits. Methods30 rabbits were subjected to ballooninduced abdominal aortic wall injuries and then were fed with a dietary of 1% cholesterol. After 10 weeks induction, they were randomly divided into three groups: the regression group, the Tongxinluo group and the simvastatin group. At the end of week 24, recombinantp53 adenoviruses were locally delivered to the atherosclerotic plaques and plaque rupture was triggered by the intraarterial viper venom and histamine. The serum lipids, the high frequency duplex, the acoustic densitometry and the pathologic staining were all determined. ResultsCompared with the regression group, TC, LDL-C（P＜0.01）and IMT （P＜0.050.01）in the Tongxinluo group and the simvastatin group were significantly decreased while the AIIc %（P＜0.050.01）was significantly increased. The TC level in the simvastatin group was lower than that in the Tongxinluo group（P＜0.01）. Conclusion Both Tongxinluo and simvastatin can increase the stability of atherosclerosis in rabbits with vulnerable plaques.

Key words: Vulnerable plaque, Tongxinluo, Simvastatin