 This project is designed to evaluate the molecular mechanisms involved in the early development of endothelial dysfunction in type 2 diabetic patients. The investigators intend to correlate increases in insulin signaling pathway activity following pioglitazone therapy with improvements in nitric oxide synthase expression in skeletal muscle. In addition, the investigators will evaluate vascular responses and in vivo nitric oxide release during administration of acetylcholine and nitroprusside in patients with type 2 diabetes. Enhanced knowledge of the molecular mechanisms responsible for endothelial dysfunction, an early abnormality in the pathogenesis of atherosclerosis, is critical before novel therapies to arrest or delay the appearance of cardiovascular complications in diabetes can be developed. 