Carotid sinus pulse pressure, a determinant of plasma antidiuretic hormone concentration

Abstract

The carotid sinuses of the anesthetized, vagotomized dog were perfused with an exaggerated pulse pressure. When the carotid sinus perfusion pressure was changed from pulsatile to essentially nonpulsatile, mean systemic arterial pressure increased 56%. The plasma concentration of antidiuretic hormone (ADH) increased 89%, even though there was a small elevation in mean sinus perfusion pressure. E mean systemic arterial pressure was prevented from rising when the sinus perfusion pressure was changed from pulsatile to steady, the plasma ADH titer rose 166%. In this situation there was no change in mean sinus perfusion pressure. Other investigators have demonstrated that a decrease in intrasinusal pulse pressure, mean sinus pressure remaining constant, results in a decreased activity of the carotid sinus baroreceptors. Therefore it is concluded that a reduction in carotid sinus baroreceptor activity results in decreased inhibition of the release of ADH from the neurohypophysis. This, in turn, results in an elevation in the plasma ADH level.