Abstract:Aim To investigate the effects and potential mechanisms of atorvastatin on atherosclerotic lesion of hypercholesterolemic rabbits. Methods Fourteen male New Zealand rabbits were randomly divided into normal diet group(n=4),high-cholesterol diet group(n=10).After 8 weeks,highcholesterol diet rabbits were randomly switched to receive either atorvastatin 1.5 mg/(kg·d)(n=5) or starch(n=5).Two weeks later,the aortas of all rabbits were removed under deep anesthetization.The distal portion of aorta to the iliac bifurcation was exercised for hematoxylin-eosin staining and monocyte chemotactic protein-1(MCP-1) mRNA detection by in-situs hybridization. Atherosclerotic area,intima and media thickness were measured by experienced pathologist using Beihang pathology imaging analysis system.MCP-1 expression was expressed as average positive cell counts per ten HP. Plasma interleukin(IL-6) levels were determined by enzyme-linked immunosorbent assay(ELISA). Results Plasma IL-6 levels positively correlated with plasma low density lipoprotein cholesterol(LDLC) levels(r=0.852,p<0.01). Compared with starch group,atorvastatin treatment decreased plasma IL-6 levels by 55% and resulted in the decreased atherosclerotic area(52.5%±4.2% vs 81.9%±2.8%,p<0.01) and reduced intimae thickness(24.18±10.21 μm vs 77.51±22.47 μm,p<0.01).Additionally,atorvastatin treatment led to MCP1 positive cell counts decreased in aorta intimae(29±5 /HP vs 49±17 /HP,p<0.01).Intimae thickness of aorta was positively correlated with MCP-1 mRNA expression in intimae(r=0.831,p<0.01). Conclusion Hypercholesterolemia may induce systemic inflammation.Atorvastatin treatment can take anti-atherosclerotic effects possibly through reducing plasma cholesterol levels and inhibiting plasma IL-6 and MCP-1 expression in intima.