Objective: To explore the roles of persistent systemic inflammation in atherosclerosis and the effects of saponins of Panax Notoginseng (PNS) on this process in rabbits. Methods: Thirty rabbits were divided randomly and equally into 6 groups, i.e., control, high-fat diet, inflammation, aspirin, PNS and simple-inflammation group. All the animals except that in control group and simple-inflammation group were fed with high-fat diet for 8 weeks. Based on that, rabbits in inflammation, aspirin and PNS groups were treated with zymosan injection (10 mg/kg, i.p.). Normal saline was given to rabbits in control group. Besides zymosan injection, animals in aspirin and PNS group were administrated with aspirin (12 mg/kg, i.g.) and PNS (120 mg/kg, i.g.) respectively. The animals in simple-inflammation group were treated with zymosan injection (10mg/kg, i.p.) and fed with normal diet. The atherosclerosis lesion in aortas was observed by Sudan IV staining. Serum total cholesterol, triglyceride (TG), TNF-α and activity of post-heparin lipoprotein lipase (LPL) were measured at the end of the 4th and 8th week after an overnight fast. Results: Compared with high-fat diet group, the area of atherosclerosis lesion, serum TG and TNF-α were markedly increased in rabbits of inflammation group, and the activity of LPL was decreased remarkably. Serum TNF-α level was negatively correlated with the activity of post-heparin LPL (r=0.708, P〈0.01). The area of atherosclerosis, serum TG and TNF-α were decreased in aspirin and PNS group compared with that in inflammation group, and the activity of LPL was increased remarkably. Compared with control group, serum TG and TNF-α were markedly increased in simple-inflammation group, while LPL activity was decreased. Atherosclerotic lesion did not occur in simple-inflammation group. Conclusion: Persistent systemic inflammation could accelerate the formation of atherosclerosis lesion in aortas, which partly depend on the decreasing of the activity of post-