Hormonal responses to gradual changes in dietary sodium intake in humans.
The effects of gradual (50 mmol/day) increases in dietary sodium intake from 10 to 350 mmol/day on plasma atrial natriuretic peptide (ANP), aldosterone, and plasma renin activity (PRA) were studied in six normal subjects. With the increases in sodium intake there was a progressive increase in urinary sodium from 12.2 +/- 4.4 to 314.8 +/- 31.4 mmol/24 h; plasma ANP increased gradually from 9.9 +/- 1.1 to 23.3 +/- 2.2 pg/ml, with the increases being closely associated with the changes in cumulative sodium balance. Plasma aldosterone decreased significantly from 2,519.7 +/- 147.4 pmol/l on the 10 mmol/day to 1,393.3 +/- 125.4 pmol/l when the sodium intake was increased to 50 mmol/day and decreased further to 251.6 +/- 78.7 pmol/l by the end of the study. The changes in PRA paralleled those in plasma aldosterone with the exception of no significant change in plasma PRA within 24 h of the initial increase in sodium intake. This marked sensitivity in the responses of both the ANP and the renin-aldosterone system to small increases in sodium intake clearly points to their importance in the renal adaptations to alterations in dietary sodium intake.
Sagnella
G A
GA
Department of Medicine, Charing Cross and Westminster Medical School, London, United Kingdom.
Markandu
N D
ND
Buckley
M G
MG
Miller
M A
MA
Singer
D R
DR
MacGregor
G A
GA
D000328:Adult; D000450:Aldosterone / Q000097:blood*; D009320:Atrial Natriuretic Factor / Q000097:blood*; D001794:Blood Pressure / Q000187:drug effects; D001798:Blood Proteins / Q000032:analysis; D003404:Creatinine / Q000097:blood; D004231:Diuresis / Q000187:drug effects; D005260:Female; D006801:Humans; D007700:Kinetics; D008297:Male; D011188:Potassium / Q000097:blood / Q000652:urine; D012083:Renin / Q000097:blood*; D012964:Sodium / Q000097:blood; D012982:Sodium, Dietary / Q000494:pharmacology*
D001798:Blood Proteins; D012982:Sodium, Dietary; D000450:Aldosterone; D009320:Atrial Natriuretic Factor; D012964:Sodium; D003404:Creatinine; D012083:Renin; D011188:Potassium