Dietary sodium intake and vasopressin excretion in man

The present study was undertaken to examine the possible relationship between dietary sodium intake and arginine vasopressin (AVP). In 12 normotensive men (aged 23-26 years) urinary AVP excretion decreased from 6.7 +/- 1.0 to 3.9 +/- 0.3 ng/h (P less than 0.01) when sodium excretion by dietary intervention for one week was reduced from 188 +/- 18 to 16 +/- 2 mmol/24 h. At a high sodium intake (300 mmol/day), AVP excretion increased to 10.0 +/- 1.2 ng/h during the first day (P less than 0.01) and remained high throughout one week of sodium load. These results are compatible with a major physiological role of sodium in AVP secretion in man. A sodium-AVP relationship may play a role in the pathogenesis of essential hypertension since recent reports suggest elevated plasma AVP in essential hypertensive states.