On the relationship between cardiac output and peripheral arterial resistance

The concept of 'whole body auto-regulation' is a somewhat unsatisfactory explanation of the increased peripheral arterial resistance which follows a rise in cardiac output in 'volume' forms of hypertension. This analysis suggests that the resistance change may be due to the sodium retention and increased cardiac output having a direct effect to alter haemodynamics of flow through the arterioles in such a way as to damage their walls, and so lead to the gradual development of structural arteriolar narrowing. Studies are presented in the DOCA/salt hypertensive rat consistent with this proposal.