Physiological Significance of Atrial Natriuretic Peptides in Essential Hypertension : SYMPOSIUM ON ATRIAL NATRIURETIC POLYPEPTIDE (ANP): Basic and Clinical Research : 51th Annual Scientific Session of the Japanese Circulation Society

Abstract

To investigate the significance of atrial natriuretic peptides (ANP) in essential hypertension, plasma ANP concentrations in 43 essential hypertensives, 16 borderline hypertensives and 17 normotensive controls were measured. Furthermore, effects of high-sodium and low-sodium intakes on plasma ANP concentration were examined in "salt-sensitive" [SS] and "nonsalt-sensitive" [NSS] patients with essential hypertension. Plasma ANP concentration was significantly higher in hypertensives than in borderline hypertensives and in normotensive controls. No significant difference in plasma ANP concentration was observed between borderline hypertensives and normotensive controls. Plasma ANP concentration increased with the high-sodium diet in both the SS and NSS patients, but the mean increment was significantly greater in the SS than the NSS patients. Urinary excretion of sodium was lower in the SS patients taking the high-sodium diet than the coresponding value in the NSS patients. These findings suggest that an increased level of circulating ANP in hypertensive patients represents a compensatory mechanism to offset further elevation of blood pressure and sodium retention.