Angiotensin converting enzyme inhibition and angiotensin II AT1-receptor blockade reduce the levels of asymmetrical NG, NG-dimethylarginine in human essential hypertension1

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 micromol/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 micromol/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.