Reestablishing blood flow (reperfusion) to organs that had their blood supply restricted (ischemia) can cause damage to the vasculature via injury and tissue death resulting in endothelial dysfunction. This ischemia-reperfusion (blood flow occlusion and resupply) triggered injury can be reduced or prevented by preceding brief periods of ischemia called preconditioning. Properly-performed preconditioning can exert a powerful protection against a subsequent sustained period of ischemia in a variety of organs in the body including the heart, kidney, and skeletal muscle. Preconditioning protocol involves repeated brief inflation and deflation of a blood pressure cuff. In many of human cardiovascular research studies, it is common to measure endothelial function and ambulatory (24-hour) blood pressure. The ambulatory blood pressure device takes repeated blood pressure readings every 15-30 minutes during the daytime and 30-60 minutes at night. It is possible that repeated bouts of inflation/deflation of the blood pressure cuff could induce preconditioning effects and influence endothelial function. Therefore, in the proposed study we aim to address this hypothesis.
