title: Captopril does not scavenge superoxide: captopril prevents O2-. production by chelating copper.
abstract: The purpose of this study was to use a direct method, that of electron spin resonance spectroscopy, to evaluate the ability of captopril, an angiotensin-converting enzyme inhibitor, to prevent the superoxide-mediated formation of phenyl radicals. Results indicate that, under certain conditions, captopril is a potent inhibitor of the generation of phenyl radicals, produced by the autoxidation of phenylhydrazine. The inhibitory effect of captopril, however, was better understood as a direct interaction of the drug with the metals that catalyze the autoxidation process rather than as a reaction of captopril with the free radicals generated. This last conclusion was supported by the finding that captopril was not able to inhibit the superoxide anion-mediated reduction of nitroblue tetrazolium.
authors.affiliation: Departamento de Bioquímica, Instituto Nacional de Cardiología, Ignacio Chávez, México City, México.
authors.forename: D
authors.initials: D
authors.lastname: Jay
authors.forename: A
authors.initials: A
authors.lastname: Cuéllar
authors.forename: R
authors.initials: R
authors.lastname: Zamorano
authors.forename: E
authors.initials: E
authors.lastname: Muñoz
authors.forename: R
authors.initials: R
authors.lastname: Gleason
mesh_terms: D002216:Captopril / Q000494:pharmacology*; D002614:Chelating Agents / Q000494:pharmacology*; D003300:Copper / Q000737:chemistry*; D004578:Electron Spin Resonance Spectroscopy; D016166:Free Radical Scavengers; D010084:Oxidation-Reduction / Q000187:drug effects; D010659:Phenylhydrazines / Q000737:chemistry; D013482:Superoxide Dismutase / Q000494:pharmacology; D013481:Superoxides / Q000737:chemistry* / Q000494:pharmacology
chemical_list: D002614:Chelating Agents; D016166:Free Radical Scavengers; D010659:Phenylhydrazines; C030299:phenylhydrazine; D013481:Superoxides; D003300:Copper; D002216:Captopril; D013482:Superoxide Dismutase