Perspective on the physiology of hypertension

Present understanding of the physiology of arterial pressure regulation indicates that the renal-body fluid volume system determines the level at which the mean pressure resides over long periods of time. The relationships between blood volume, and size and compliance of the entire vascular system, and intrinsic regulation of tissue blood flow determine the sequence of observed changes in cardiac output and total peripheral resistance. Current evidence is compatible with the concept that functional changes in the renal vasculature or tubular system, either intrinsic or extrinsic in origin, reflect the final common pathway in the genesis of all forms of experimental and human hypertension. At the present time the nature of these renal changes appears to alter the fundamental relationships between renal perfusion pressure and sodium and water excretion. One of the major challenges in the field of hypertension today is to test the hypothesis that changes in renal function, either extrinsic or intrinsic in form, are involved in all forms of hypertension.