Abstract: Objective To explore effects of rosuvastain on expressions of matrix metalloproteinase-2(MMP-2)and matrix metalloproteinase-9(MMP-9)in vulnerable plaque in rabbits.Methods Fourty healthy male New Zealand white rabbits were randomly divided into four groups:control group(n=10),vulnerable plaque group(n=10),low dose rosuvastatin group(n=10,1 mg/kg/d)and high dose rosuvastatin group(n=10,2 mg/kg/d).Total cholesterol(TC),low-density lipoprotein cholesterol(LDL-C),high-density lipoprotein cholesterol(HDL-C),and triglyceride(TG)were detected before and 1 month after the treatment,respectively.At the end of experiment,all rabbits were sacrificed and expressions of MMP-2 and MMP-9 were determined with immunohistochemical assays.Results Compared to the control group,the concentrations of TC,TG,and LDL-C significantly decreased in rosuvastain treatment groups(11.93±0.35 and 13.73±0.35 mmol/L,6.24±0.37 and 7.53±0.36 mmol/L,and 4.28±0.23 and 4.83±0.25 mmol/L for high dose and low dose group);the concentration of HDL-C increased significantly(1.93±0.24 for high dose group and 1.62±0.22 mmol/L for low dose group)(P<0.05 for all).The results of immunohistochemical assays showed that the expressions of MMP-2 and MMP-9 in unstable plague of abdominal aorta were significantly decreased in high and low dose rosuvastatin treatment groups(P<0.05 for all)compared to that of control group.ConclusionRosuvastatin improves blood lipid levels and reduces expressions of MMP-2 and MMPv9 which might stabilize the atherosclerotic plaques in rabbits.