Long-term effects of captopril (SQ14 225) on blood-pressure and hormone levels in essential hypertension.
Captopril, an orally active angiotensin-converting enzyme (ACE) inhibitor, was effective in the long-term reduction of blood-pressure in 17 patients with essential hypertension. The addition of hydrochlorothiazide produced a further hypotensive effect, and the combined treatment produced satisfactory control of the blood-pressure for eight months. Captopril prevented and reversed the secondary hyperaldosteronism and hypokalaemia induced by simultaneous diuretic administration, thus eliminating the need for potassium supplements. The fall in plasma-angiotensin-II and urinary aldosterone and rise in angiotensin I and plasma-renin provide biochemical evidence that captopril inhibits ACE in vivo. No change in circulating venous bradykinin levels could be detected. The hypotensive action of captopril is not mediated by changes in blood-bradykinin but may involve inhibition of the renin-angiotensin and kallikrein-kinin systems locally within the kidneys or blood vessels.
D000328:Adult; D000368:Aged; D000803:Angiotensin I / Q000097:blood; D000804:Angiotensin II / Q000037:antagonists & inhibitors; D001794:Blood Pressure / Q000187:drug effects; D001920:Bradykinin / Q000097:blood; D002216:Captopril / Q000627:therapeutic use*; D004357:Drug Synergism; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006852:Hydrochlorothiazide / Q000627:therapeutic use; D006973:Hypertension / Q000188:drug therapy* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D000451:Mineralocorticoid Receptor Antagonists; D011188:Potassium / Q000097:blood; D011392:Proline / Q000031:analogs & derivatives*; D012083:Renin / Q000097:blood
D000451:Mineralocorticoid Receptor Antagonists; D006852:Hydrochlorothiazide; D000804:Angiotensin II; D000803:Angiotensin I; D011392:Proline; D002216:Captopril; D012083:Renin; D011188:Potassium; D001920:Bradykinin