Role of Reflexes from the Heart in the Control of the Circulation under Stressful Conditions.
Final rept. 1 Sep 73-31 Dec 74,
UNIVERSITY OF SOUTHERN CALIFORNIA LOS ANGELES DEPT OF PHYSIOLOGY
Pagination or Media Count:
Obtained data indicated that a specific decrease in atrial receptor activity caused the release of antidiuretic hormone ADH. In the absence of changes in arterial hemodynamics, a marked drop in urine flow occurred with atrial tamponade. The change in urine flow was entirely due to a decreased water clearance and was not accompanied by marked changes in osmotic clearance as confirmed by no changes in sodium and potassium excretion. The afferent mechanism for the decrease in water excretion is felt to be a specific decrease in atrial recepter activity since there were no significant changes in arterial mean or pulse pressures. The efferent mechanism is unclear since a decrease in renal flow occurred concomitantly with inflation of the atrial tamponade. Two indirect techniques--inflation of a balloon device in the left atrium and infusion of norepinephrine during atrial tamponade--suggest the antidiuresis is due to release of ADH.
- Anatomy and Physiology