At baseline, before initiating glitazone treatment, clinical data will be recorded and blood samples will be obtained for biological measurements (blood glucose, HbA1c, total cholesterol, triglycerides, LDL-cholesterol, HDL-cholesterol, liver enzymes), phospholipase A2 measurement and the study of the vasodilatory effect of HDL particles.For this purpose, we will study,using rabbit aorta rings,the ability of HDL to suppress the inhibition of vasodilation that is induced by oxidised LDL.