L-Arginine inhibits xanthine oxidase-dependent endothelial dysfunction in hypercholesterolemia

Academic Article


  • Xanthine oxidase (XO)-derived superoxide contributes to endothelial dysfunction in humans and animal models of hypercholesterolemia (HC). Since L-arginine supplementation prevents defects in NO signaling, we tested the hypothesis that L-arginine blunts the inhibitory effect of XO on vascular function. Acetylcholine-mediated relaxation was significantly impaired in ring segments of HC rabbits, a response that was associated with an increase in plasma XO activity. L-Arginine treatment of HC rabbits reduced plasma XO and improved endothelial function. L-Arginine also modestly prolonged the lag time for oxidation in isolated lipoprotein samples. These results reveal that the principal action of L-arginine is to protect against the XO-dependent inactivation of NO in arteries of HC rabbits. © 2004 Published by Elsevier B.V. on behalf of the Federation of European Biochemaical Societies.
  • Published In

  • FEBS Letters  Journal
  • Digital Object Identifier (doi)

    Author List

  • White CR; Parks DA; Patel RP; Shelton J; Tarpey MM; Freeman BA; Darley-Usmar VM
  • Start Page

  • 94
  • End Page

  • 98
  • Volume

  • 561
  • Issue

  • 1-3