title: Evaluation of the antioxidant properties of the angiotensin-converting enzyme inhibitor, captopril and the nucleotide enhancing agent, acadesine.
abstract: The angiotensin-converting enzyme inhibitor, captopril and the nucleotide enhancing agent, acadesine, protect myocardial tissue from ischaemia/reperfusion-induced injury. Although both drugs have well established, independent mechanisms of cardiac protection, they may also have antioxidant activity which could contribute to their beneficial action. In this study we have examined the antioxidant activity of captopril and acadesine by examining their ability to scavenge ABTS radicals, formed from the interaction of ferryl metmyoglobin with phenothiazine in the presence of hydrogen peroxide. For comparison, we compared these results to those obtained for a range of other drugs commonly used for the treatment of cardiovascular disorders. These included verapamil (arrhythmia), isosorbide dinitrate (angina), atenolol (hypertension) and enalapril (congestive heart failure). The antioxidant properties of these drugs were then compared to the well characterised antioxidants, Trolox (a water soluble vitamin E analogue), ascorbate and glutathione. Captopril and acadesine were both shown to be efficient scavengers of ABTS radicals, importantly at drug concentrations expected to be found in vivo. These data confirm that the antioxidant potential of captopril and acadesine may be an important component of their mechanism of action, with both drugs probably protecting the myocardium against oxygen derived free radicals during ischaemia/reperfusion.
authors.affiliation: a Cardiovascular Research , The Rayne Institute, St Thomas' Hospital Medical School , London , UK.
authors.forename: M
authors.initials: M
authors.lastname: Wasil
authors.affiliation: a Cardiovascular Research , The Rayne Institute, St Thomas' Hospital Medical School , London , UK.
authors.forename: F J
authors.initials: FJ
authors.lastname: Kelly