Water and Salt Excretion after Intravenous Salt Load in Hypertensive Subjects

Abstract

Intravenous salt-loading tests were performed in 20 hypertensive and 31 normotensive subjects. During the following 5 half-hour collection periods both water and salt excretion by the hypertensive subjects was higher than by the normotensive ones. The diuretic response was much more prolonged and more pronounced than the saluretic response and appears to be a primary response to the salt load, characteristic of the hypertensive state. The increased salt excretion is in part to be explained as the consequence of the increased water excretion. At moderate flow rates a salt-retaining mechanism could be demonstrated which is obscured at the higher rates of urinary flow that usually follow the salt load.