title: Inactivation of alpha 1-antiproteinase by hydroxyl radicals. The effect of uric acid.
abstract: The elastase-inhibitory activity of alpha 1-antiproteinase is inactivated by hydroxyl radicals (.OH) generated by pulse radiolysis or by reaction of iron ions with H2O2 in the presence of superoxide or ascorbate. Uric acid did not protect alpha 1-antiproteinase against inactivation by .OH in pulse radiolysis experiments or in the superoxide/iron/H2O2 system, whereas it did in systems containing ascorbic acid. We propose that radicals formed by attack of .OH on uric acid are themselves able to inactivate alpha 1-antiproteinase, but that these uric acid radicals can be 'repaired' by ascorbic acid.
authors.affiliation: Department of Biochemistry, University of London, King's College, England.
authors.forename: O I
authors.initials: OI
authors.lastname: Aruoma
authors.forename: B
authors.initials: B
authors.lastname: Halliwell
mesh_terms: D001205:Ascorbic Acid; D001798:Blood Proteins / Q000037:antagonists & inhibitors*; D055598:Chemical Phenomena; D002621:Chemistry; D004492:Edetic Acid; D006861:Hydrogen Peroxide; D006863:Hydrogen-Ion Concentration; D006878:Hydroxides / Q000494:pharmacology*; D017665:Hydroxyl Radical; D019271:Hypoxanthine; D007042:Hypoxanthines; D007213:Indomethacin / Q000494:pharmacology; D007501:Iron; D009609:Nitrous Oxide; D010196:Pancreatic Elastase / Q000037:antagonists & inhibitors; D010894:Piroxicam / Q000494:pharmacology; D011480:Protease Inhibitors; D011675:Pulse Radiolysis; D013481:Superoxides; D014527:Uric Acid / Q000494:pharmacology*; D014969:Xanthine Oxidase; D000515:alpha 1-Antitrypsin
chemical_list: D001798:Blood Proteins; D006878:Hydroxides; D007042:Hypoxanthines; D011480:Protease Inhibitors; D000515:alpha 1-Antitrypsin; D013481:Superoxides; D010894:Piroxicam; D014527:Uric Acid; D019271:Hypoxanthine; D017665:Hydroxyl Radical; D004492:Edetic Acid; D006861:Hydrogen Peroxide; D007501:Iron; D014969:Xanthine Oxidase; D010196:Pancreatic Elastase; D009609:Nitrous Oxide; D001205:Ascorbic Acid; D007213:Indomethacin