Inhibitory Effect of HMG-CoA Reductase Inhibitors for the Development and Progression of Intimal-medial Thickness in Carotid Artery in Type 2 Diabetes Mellitus with Hypercholesterolemia

We have in vitro reported that HMG-CoA reductase inhibitors suppressed macrophage growth induced by oxidized-low density lipoproteins. On the other hand, Sahni et al demonstrated that lovastatin inhibited rat smooth muscle cell proliferation. Therefore, in vivo, to elucidate whether HMG-CoA reductase inhibitors have anti-atherogenic effect except for cholesterol-lowering effect, level of plasma total cholesterol in type:! diabetes mellitus (type2 DM) with hypercholesterolemia was decreased until normal level for one year using HMG-CoA reductase inhibitors and measured intima-medial thickness (IMT) in carotid arteries. Type2 DM with hypercholesterolemia was divided to pravastatin-treatment group and simvastatin-treatment group, as compared with type2 DM with normocholesterolemia. IMT in carotid artery was measured using Powervision SSA-370A, probe 7.5Mhz (TOSHIBA Co.LTD). Mean IMT and the increasing rate were relatively elevated in the order of simvastatin-treatment group, pravastatin-treatment group, and control group. From this result, it is suggested that HMG-CoA reductase inhibitors may have anti-atherogenic effect except for cholesterol-lowering effect.