title: Antihypertensive efficacy of once daily MK-521, a new nonsulfhydryl angiotensin-converting enzyme inhibitor.
abstract: The effects of the new nonsulfhydryl-containing oral converting-enzyme inhibitor MK-521 on blood pressure, heart rate, angiotensin-converting enzyme activity, plasma renin activity and plasma aldosterone concentration were assessed in 10 hypertensive patients. After a 2-week no-treatment period, patients received placebo and then 14 days each: MK-521 20 mg once daily, hydrochlorothiazide 50 mg once daily and the latter 2 in combination. During the last day of each treatment, the mean (+/- standard deviation) time-averaged (1- to 12-hour) standing diastolic blood pressure decreased from 106 +/- 8 (placebo) to 95 +/- 10 mm Hg with MK-521, 95 +/- 13 mm Hg with hydrochlorothiazide (p less than 0.05 vs placebo) and 88 +/- 11 mm Hg with the combination (p less than 0.05 vs all other treatments). The antihypertensive effect of MK-521 was maintained 24 hours after dosing. Heart rate did not change significantly after MK-521 treatment. MK-521 caused a marked suppression of converting enzyme activity for over 24 hours; plasma renin activity increased significantly after each active treatment and MK-521 significantly decreased the hydrochlorothiazide-induced elevation of plasma aldosterone concentration. In this short-term trial, MK-521 was well tolerated.
mesh_terms: D000328:Adult; D000368:Aged; D000806:Angiotensin-Converting Enzyme Inhibitors; D001794:Blood Pressure; D002986:Clinical Trials as Topic; D004151:Dipeptides / Q000008:administration & dosage* / Q000009:adverse effects; D005260:Female; D006801:Humans; D006852:Hydrochlorothiazide / Q000627:therapeutic use; D006973:Hypertension / Q000175:diagnosis / Q000188:drug therapy* / Q000201:enzymology; D017706:Lisinopril; D008297:Male; D008875:Middle Aged; D007703:Peptidyl-Dipeptidase A / Q000097:blood; D011674:Pulse; D012083:Renin / Q000097:blood
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D004151:Dipeptides; D006852:Hydrochlorothiazide; D017706:Lisinopril; D007703:Peptidyl-Dipeptidase A; D012083:Renin