The objective of this study was to elucidate the mechanisms of mitochondrial @entity274 generation in @entity19 organs by determining the nature of their differences in substrate utilization, inhibitor sensitivity, and the site specificity affecting @entity274 production. Mitochondria were isolated from heart, brain, and kidney and the rate of @entity274 generation was measured using the @entity44401 -linked substrates @entity4588 and @entity7685 as well as the @entity2125 -linked substrates @entity2388 / @entity5910 , @entity4322 , and @entity2227 . Respiratory inhibitors, @entity11382 and @entity3788 , were added singly and sequentially to each substrate-supported @entity274 generation reaction mixture to determine the mitochondrial site(s) of generation and the optimal condition(s) for maximal rates of generation. @entity4588 supported the highest rate of mitochondrial @entity274 generation. Moreover, it was the preferred substrate for the heart mitochondria. @entity7685 is a poor substrate for @entity274 generation in heart mitochondria. Inhibitor studies showed that heart mitochondria were the most sensitive and responsive to antimycin, while brain was the most sensitive to @entity3788 . A surprising finding was that @entity2125 -linked substrate-supported @entity274 generation in kidney mitochondria was not responsive to @entity3788 . The contribution from each of the three sites ( @entity12931 , @entity2125 dehydrogenase, and @entity7685 dehydrogenase) of mitochondrial @entity274 generation to the total was both substrate and organ dependent. Results indicate that assay conditions must be considered before comparisons of sites and rates of mitochondrial @entity274 generation among different organs can be made.

Substrate and site specificity of hydrogen peroxide generation in XXXX mitochondria.

@entity2125 :: ('MESH:D009243', 'Chemical') :: ['NADH'] @entity2227 :: ('CHEBI:29987', 'Chemical') :: ['glutamate'] @entity274 :: ('CHEBI:16240', 'Chemical') :: ['H2O2'] @entity12931 :: ('MESH:D014451', 'Chemical') :: ['ubiquinone'] @entity19 :: ('10090', 'Species') :: ['mouse'] @entity4588 :: ('MESH:D019802', 'Chemical') :: ['succinate', 'Succinate'] @entity3788 :: ('MESH:D012402', 'Chemical') :: ['rotenone'] @entity5910 :: ('MESH:C030298', 'Chemical') :: ['malate'] @entity4322 :: ('MESH:D020155', 'Chemical') :: ['beta-hydroxybutyrate'] @entity11382 :: ('MESH:C032456', 'Chemical') :: ['antimycin'] @entity7685 :: ('MESH:C029620', 'Chemical') :: ['alpha-Glycerophosphate', 'alpha-glycerophosphate'] @entity2388 :: ('MESH:D019289', 'Chemical') :: ['pyruvate'] @entity44401 :: ('CHEBI:30788', 'Chemical') :: ['FADH']
@entity19 :: (10090,Species) :: ['mouse']
