title: Enalapril (MK421) and its lysine analogue (MK521): a comparison of acute and chronic effects on blood pressure, renin-angiotensin system and sodium excretion in normal man.
abstract: The immediate and long-term effects of enalapril (MK421) and its lysine analogue (MK521) in once-daily dosage, were compared in a study of 12 normal subjects. Both compounds lowered blood pressure equally throughout 24 h without causing tachycardia. The biochemical changes with MK521 were more sustained than with MK421, but this did not affect the magnitude of blood pressure reduction. Twenty-four hours after the previous dose, with both active drugs, plasma renin concentration was significantly higher on day 8 than on day 1, though angiotensin I did not increase in proportion; this probably reflects a fall in renin-substrate with prolonged converting enzyme inhibition. There was an early natriuresis with each compound but this effect was no longer apparent after 8 days of continuous therapy. Both MK421 and MK521 were well tolerated with no serious side effects.
mesh_terms: D000328:Adult; D001794:Blood Pressure / Q000187:drug effects*; D004151:Dipeptides / Q000009:adverse effects / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004573:Electrolytes / Q000097:blood; D004656:Enalapril; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D017706:Lisinopril; D008297:Male; D009318:Natriuresis / Q000187:drug effects*; D012084:Renin-Angiotensin System / Q000187:drug effects*; D013997:Time Factors
chemical_list: D004151:Dipeptides; D004573:Electrolytes; D004656:Enalapril; D017706:Lisinopril