Effects Of Pravastatin On Atherosclerotic Plaque Stability And Mechanism In ApoE KO Mice

Objective: To investigate the effects of pravastatin on atherosclerotic plaque stability and mechanism in ApoE KO mice.Methods: Eight ApoE KO mice were randomly divided into two groups,control group and pravastatin(40 mg/kg/d)treated group.Blood from each mouse(35 weeks)drawn from heart directly for tests of the serum level of lipids.Then,the mice were killed and the aorta were obtained.Aorta specimens were obtained by Oil Red‘O'and to examine the size of plaques within two groups.Then the atherosclerotic plaques were section for making tissue microarray and hematoxylin & eosin(HE)staining to explore the pathological process.Observing M1(iNOS)and M2(Arg-1)macrophages in atherosclerotic calcified and non-calcified plaques,control and pravastatin treated groups through immunohistochemistry.Results: Compared with the control group,the pravastatin treated group elevated blood cholesterol levels and increased atherosclerotic plaques size.We also find a lower M1/M2 macrophages ratio in region of calcified compared to non-calcified plaques.Besides,the increase of plaque calcification and the decrease of M1/M2 macrophages ratio were observed in pravastatin treated group.Conclusion: These results imply that pravastatin could increase plaque stability through lipid-independent way.Pravastatin have an effect of stabilization of plaques through promoting calcification and changing the balance of M1 and M2 macrophages in atherosclerotic plaques.