Pravastatin inhibits plaque rupture and subsequent thrombus formation in atherosclerotic rabbits with hyperlipidemia

Previous studies have demonstrated that statin can reduce the risk of acute coronary syndrome. In order to explore the mechanism, we observed the effects of pravastatin on plaque stability in atherosclerotic rabbits. Sixteen male rabbits were fed with a high fat diet following their damaged abdominal aortic endothelium by using catheter. Eight of them were administered with pravastatin (10 mg·kg(-1)·d(-1)) for 4 weeks. Then the rabbit atherosclerotic plaque rupture and thrombosis were triggered by injection of viper venom and histamine. Compared with model group, the thrombus area on aorta in pravastatin-treated group was reduced. Fibre cap on plaque was more thick and integrant, and inflammatory cell infiltration was also decreased. Serum total cholesterol, triglyceride, low density lipoprotein-cholesterol and contents of cholesterol in abdominal aorta were decreased. 6-Keto-prostaglandin F(1α) (6-keto-PGF(1α)) level and ratio of 6-keto-PGF(1α)/thromboxane B(2) (TXB(2)) in aorta were significantly increased. These results suggested that pravastatin could increase plaque stability and inhibit thrombosis through both lipid-dependent and lipid-independent way.