title: NAD(P)H- and superoxide-dependent nitric oxide degradation by rat liver mitochondria.
abstract: Mitochondria consume nitric oxide (NO) mainly through reaction with superoxide anion (O(2)(-)). Here, we analyzed the O(2)(-) sources for NO degradation by isolated rat liver mitochondria. Electron leakage from complex III and reverse electron transport to complex I accounted for O(2)(-)-dependent NO degradation by mitochondria in the presence of a protonmotive force. Mitochondria incubated with NAD(P)H also presented intense O(2)(-) generation and NO degradation rates that were insensitive to respiratory inhibitors and abolished after proteinase treatment. These results suggest that an outer membrane-localized NAD(P)H oxidase activity, in addition to the electron leakage from the respiratory chain, promotes O(2)(-)-dependent NO degradation in rat liver mitochondria.
authors.affiliation: Departamento de Biologia Vegetal, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Campinas, SP, Brazil.
authors.forename: Halley Caixeta
authors.initials: HC
authors.lastname: Oliveira
authors.forename: Elzira Elisabeth
authors.initials: EE
authors.lastname: Saviani
authors.forename: Ione
authors.initials: I
authors.lastname: Salgado
mesh_terms: D000818:Animals; D008297:Male; D008930:Mitochondria, Liver / Q000378:metabolism*; D009243:NAD / Q000378:metabolism*; D019255:NADPH Oxidases / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D013481:Superoxides / Q000378:metabolism*
chemical_list: D009243:NAD; D013481:Superoxides; D009569:Nitric Oxide; D019255:NADPH Oxidases