Regulatory mechanisms of arterial compliance and endothelial function in humans

点击翻译按钮获取中文摘要

Most of us realize that our blood vessels play an important role in transporting blood to and from all of the tissues of our body. Blood vessels are, however much more than static tubes for transporting blood. The structure and function of our blood vessels can adapt to challenges they are presented with and can change their level of function significantly over both short and long time frames. Two important features of our arteries (blood vessels which transport blood away from the heart) are how flexible they are and how much they can expand when faced with challenges such as increased or decreased activity level. We have techniques to assess these two features, stiffness and ability to expand, but we know very little about their regulation. In my laboratory we have been studying the role that activity, as a technique to change pressure and flow in arteries, plays in altering arterial structure and function. We now know, for example, that although aerobic exercise may temporarily impair the ability of an artery to expand in response to a challenge, over a longer time frame aerobic exercise training can increase the capacity of the same artery to expand. We are interested in following up some of our initial studies on exercise training with some studies to determine the precise factors which regulate the short term responses. We also want to start linking together the factors that regulate the structure and function of the arteries with the local blood flow at the level of the active muscles. To do this we have designed some studies which both increase and decrease local blood flow through exercise and mechanical techniques which mimic exercise. Objectives of the proposed research program include examination of the impact of alterations in artery structure and function on skeletal muscle blood flow responses both at rest, and acutely following exercise. Our continuing studies will focus on the use of cutting edge ultrasound technology to examine blood vessel stiffness and regional blood flow. The insight gained from these studies will assist in advancing the current basic knowledge of the cardiovascular system.