Effects of Changes in Dietary Sodium Intake and Saline Infusion on Plasma Atrial Natriuretic Peptide in Hypertensive Patients

Plasma concentrations of immunoreactive(IR)-atrial natriuretic polypeptide(hANP) were measured by radioimmunoassay in 9 essential hypertensive patients after alteration of salt intake and acute saline infusion. Daily salt intake was altered every one week in the order of 15g/day, 3g/day, and 7g/day. On the last day of the first week, 1500 ml of 0.9% saline was infused intravenously over one hour. Plasma concentrations of IR-hANP tended to decrease, although not significant, by salt restriction. Further, there were significant positive correlations between changes in plasma concentrations of IR-hANP and those of several variables such as body weight, systolic blood pressure, and creatinine clearance. Plasma concentrations of IR-hANP rose significantly (p