Role of aldosterone in the antihypertensive effect of spironolactone in essential hypertension.
In order to evaluate the relationship between aldosterone status and the blood pressure-lowering effect of spironolactone, 38 patients with essential hypertension were treated with spironolactone (400 mg/day) during one week in hospital on a rigidly sodium-restricted diet. The degree of hyperaldosteronism was assessed by the aldosterone secretory rate after 5 days of salt loading (315 mmol Na+/day). The mean arterial pressure decreased 5.6% (range, -21 to +8%). When the patients were divided into subgroups with low and normal renin activity, there was no difference in the change in mean arterial pressure (-5.0% and -6.1%). When the patients were divided into three groups with low, normal, and supranormal aldosterone secretory rates, the last group had a significantly greater fall in blood pressure after the spironolactone than the other groups (-1.0, -7.1, -11.1%). Thus there was a correlation between the aldosterone secretory rate after sodium loading and the blood pressure-lowering effect of spironolactone (r = -0.53, p less than 0.01). The blood pressure-lowering effect was not related to changes in body weight, kidney function, or plasma electrolytes. Our findings do not provide solid arguments for the view that the blood pressure-lowering effect of high dose spironolactone is due to its antimineralocorticoid activity, but the correlation between the degree of hyperaldosteronism and the blood pressure-lowering effect strongly suggests that aldosterone does play a role in the genesis or maintenance of the hypertension in these patients.
D000328:Adult; D000450:Aldosterone / Q000378:metabolism / Q000502:physiology*; D001794:Blood Pressure / Q000187:drug effects*; D001835:Body Weight / Q000187:drug effects; D004573:Electrolytes / Q000097:blood; D005260:Female; D006801:Humans; D006973:Hypertension / Q000378:metabolism / Q000503:physiopathology*; D007668:Kidney / Q000187:drug effects; D008297:Male; D008875:Middle Aged; D012083:Renin / Q000097:blood; D013148:Spironolactone / Q000494:pharmacology*
D004573:Electrolytes; D013148:Spironolactone; D000450:Aldosterone; D012083:Renin