More than half of patients with type 2 diabetes mellitus develop hypertension, which doubles their risk for cardiovascular disease. Inflammation plays a role in the development of these diseases, and monocytes, a type of white blood cell, may be critical. This study will isolate monocytes from blood samples of patients with type 2 diabetes and high blood pressure who have either high levels of vitamin D or low levels of vitamin D, and determine what their effects are on stimulating production in kidney cells of a hormone that increases blood pressure.