Humoral factors involved in the regulation of sodium-fluid balance in normal man. I. Effect of dietary sodium chloride intake on renal prostaglandins, vasopressin and renin-angiotensin-aldosterone system.

Animal and human studies demonstrate the dependence of renal prostaglandin (PG) production on dietary sodium chloride intake. The effect of 5 days' low salt diet (10 mmol Na/day plus 0.5 mg/kg Furanthril daily), and 5 days' high salt diet (250 mmol Na/day) on PGE2 and PGF2 alpha plasma levels and their excretion, on plasma renin activity (PRA) aldosterone (A) and vasopressin (VP) was evaluated on 30 normal subjects. Sodium restriction significantly increased plasma PGE2 and PGF2 alpha and their excretion in the urine. High salt intake reduced renal PG production to normal levels. Under low salt conditions PRA and A increased significantly and fell to normal values on high salt regimen. A negative correlation between renal PG production and VP plasma levels and excretion was demonstrated during the changes of dietary sodium intake.