title: Dopamine modifies oxygen consumption and mitochondrial membrane potential in striatal mitochondria.
abstract: Dopamine is a neurotransmitter that has been related to mitochondrial dysfunction. In this study, striatal intact mitochondria and submitochondrial membranes were incubated with different dopamine concentrations, and changes on mitochondrial function, hydrogen peroxide, and nitric oxide production were evaluated. A 35% decrease in state 3 oxygen uptake (active respiration state) was found after 1 mM dopamine incubation. In addition, mitochondrial respiratory control significantly decreased, indicating mitochondrial dysfunction. High dopamine concentrations induced mitochondrial depolarization. Also, evaluation of hydrogen peroxide production by intact striatal mitochondria showed a significant increase after 0.5 and 1 mM dopamine incubation. Incubation with 0.5 and 1 mM dopamine increased nitric oxide production in submitochondrial membranes by 28 and 49%, respectively, as compared with control values. This study provides evidence that high dopamine concentrations induce striatal mitochondrial dysfunction through a decrease in mitochondrial respiratory control and loss of membrane potential, probably mediated by free radical production.
authors.affiliation: Laboratory of Free Radical Biology, School of Pharmacy and Biochemistry, University of Buenos Aires, Junín 956, C1113AAD Buenos Aires, Argentina.
authors.forename: Analía
authors.initials: A
authors.lastname: Czerniczyniec
authors.forename: Juanita
authors.initials: J
authors.lastname: Bustamante
authors.forename: Silvia
authors.initials: S
authors.lastname: Lores-Arnaiz
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D003342:Corpus Striatum / Q000648:ultrastructure; D004298:Dopamine / Q000494:pharmacology*; D005260:Female; D005609:Free Radicals; D006861:Hydrogen Peroxide / Q000494:pharmacology; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects*; D008928:Mitochondria / Q000378:metabolism*; D009569:Nitric Oxide / Q000494:pharmacology; D010101:Oxygen Consumption / Q000187:drug effects*; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D005609:Free Radicals; D009569:Nitric Oxide; D006861:Hydrogen Peroxide; D004298:Dopamine