Plasma ProANP1–30 Reflects Salt Sensitivity in Subjects With Heredity for Hypertension

The aim of the present study was to investigate whether plasma concentration of proANP1–30, the N-terminal fragment of the atrial natriuretic peptide prohormone, or 24-hour urinary excretion of urodilatin reflects the degree of salt sensitivity in hypertension-prone individuals. Plasma concentration of proANP1–30 and urinary urodilatin excretion were determined at baseline, after 1 week on a low-salt diet (10 mmol/d) and after another week on a high-salt diet (240 mmol/d) in 30 healthy subjects with heredity for hypertension. Salt sensitivity was defined as the difference between mean arterial blood pressure after the high-salt diet and the mean arterial blood pressure after the low-salt diet. High- versus low-salt intake increased proANP1–30 (668±330 versus 358±150 pmol/L;P