This study was performed to define the extent to which atrial natriuretic factor (ANF) contributes to upregulate salt excretion in subjects eating a high-salt diet. Eight normal volunteers were first studied at low-salt diet (80 mmol NaCl/day); urinary sodium excretion (UNaV̇) and plasma ANF (PANF) were measured in the basal condition and during stepwise infusion of human α-ANF at 2, 4, 8, and 16 ng·min-1·kg-1. Then the same subjects were shifted to a high-salt diet (400 mmol/day), and UNaV̇ and PANF were measured in the new balance condition. At low-salt diet, UNaV̇ averaged 0.069 meq/min, and PANF averaged 21 pg/ ml; infusion of human α-ANF raised stepwise both UNaV̇ and PANF (means in meq/min and pg/ml, respectively, were 0.177 and 46, 0.218 and 76, 0.360 and 86, and 0.601 and 182). Infusion of ANF caused a progressive fall of plasma aldosterone and plasma renin activity. Mean UNaV̇ and PANF at high-salt diet were 0.301 meq/min and 35 pg/ml. Thus, by increasing experimentally PANF in a low-salt diet condition to the levels occurring physiologically in a high-salt diet condition, a significant rise in UNaV̇ is evoked, which accounts for ∼50% of the rise of UNaV̇ that is necessary to balance the increased salt intake.
|Journal||American Journal of Physiology - Renal Fluid and Electrolyte Physiology|
|Issue number||6 27-6|
|Publication status||Published - 1990|
- Dietary salt intake
- Sodium excretion
ASJC Scopus subject areas