Angiotensin converting enzyme inhibition and angiotensin II AT1-receptor blockade reduce the levels of asymmetrical NG, NG-dimethylarginine in human essential hypertension

Background: Asymmetrical N-G, N-G-dimethylarginine (ADMA) is associated with impaired endothelium-dependent vasodilation in humans. Methods: Twenty young, male. mildly hypertensive subjects were included in a randomized. double-blind, fourfold cross-over study with placebo, enalapril (20 mg/day), eprosartan (600 mg/day). or a combination of both drugs (10 and 300 mg/day. respectively) each over 1 week, followed by a 2-week wash-out phase. After each treatment phase, ADMA concentration was measured. Results: ADMA concentration was 1.69 +/- 0.59 mumol/L in the placebo phase, and was significantly lower in the enalapril. eprosartan. and combination phases (1.41 +/- 0.29, 1.42 +/- 0.43, and 1.38 +/- 0.30 mumol/L. respectively all P < 0.05 v placebo). Changes in ADMA levels were independent of the drugs' action on blood pressure (BP). Conclusions: Levels of ADMA were reduced with enalapril and eprosartan therapy. Our results suggest a specific action of these drugs on ADMA levels that is independent of BP. (C) 2002 American Journal of Hypertension, Ltd.