[Relations between hypotensive effect and modifications of volemia and plasma renin activity in patients with...

The hypotensive effect of spironolactone and its relation to the changer in volaemia and renin activity induced by the drug were studied in 12 hospitalised patients with essential hypertension. After 4 weeks, arterial pressure was significantly decreased in direct relation to reductions in plasma volume in 9 subjects in both the erect and the recumbent position. These reductions were probably responsible for an increase in renin activity noted (sometimes at significant levels) in all subjects. It would appear that such increase does not impede the hypotensive effect of the drug. The hypotensive response was, in fact, less marked in only 3 patients, whose basal renin levels were themselves high.