 Type 2 diabetes confers a substantial increase in the risk of cardiovascular disease. This is believed to be due, in part, to endothelial dysfunction, which correlates closely with impaired vascular responsiveness. Our study will clarify further the extent to which resistance to insulin action and impaired nitric oxide release from endothelial cells are interrelated. We also expect to demonstrate that insulin sensitizers pioglitazone can help to restore normal endothelial function, and ultimately preventdelay the appearance of vascular disease in patients with type 2 diabetes. 