Increased Bioavailability of Nitric Oxide After Lipid-Lowering Therapy in Hypercholesterolemic Patients

Abstract
Background—Impaired endothelium-dependent vasodilation is an early sign of atherosclerosis in hypercholesterolemic patients. We hypothesized that lipid-lowering therapy can improve endothelial function and that this effect is mainly mediated by increased bioavailability of nitric oxide (NO). Methods and Results—In a randomized, double-blind, placebo-controlled trial, we studied 29 patients (age, 50±12 years) with hypercholesterolemia (LDL cholesterol ≥160 mg/dL) randomly assigned to receive either fluvastatin (40 mg twice daily; 17 patients) or placebo (12 patients). Forearm blood flow was measured by plethysmography before and after 24 weeks of treatment. Endothelium-dependent vasodilation was assessed by intra-arterial infusion of acetylcholine (ACh; 3, 12, 24, and 48 μg/min) and basal NO synthesis rate by intra-arterial infusion of NG-monomethyl-l-arginine (L-NMMA; 1, 2, and 4 μmol/min). Simultaneous intra-arterial infusion of L-NMMA (4 μmol/min) and ACh (12, 24, and 48 μg/min) was used to test whether...