IBIMOL   23987
INSTITUTO DE BIOQUIMICA Y MEDICINA MOLECULAR PROFESOR ALBERTO BOVERIS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Dopamine Effects on Striatal Mitochondrial Function.
Autor/es:
CZERNICZYNIEC, A.; BUSTAMANTE, J.; LORES ARNAIZ, S.
Lugar:
Santiago de Chile, Chile
Reunión:
Congreso; Free Radicals and Antioxidants in Chile, VI Meeting of SFRBM South American Groupc; 2009
Resumen:
Dopamine is a neurotransmitter that has been related to mitochondrial dysfunction. In the present study, striatal intact mitochondria and submitochondrial membranes were incubated with different dopamine concentrations and changes on mitochondrial function and on nitric oxide production were evaluated. 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. 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. Evaluation of hydrogen peroxide production by intact striatal mitochondria showed a significant increase after 0.5 and 1 mM dopamine incubation. Also, high dopamine concentrations induced mitochondrial depolarization. Studies from different laboratories have proposed that high dopamine concentrations induce mitochondrial dysfunction by dopamine oxidation products. In our study conditions, no dopamine quinone formation was observed, suggesting that quinone formation does not seem to be involved in dopamine-induced mitochondrial dysfunction. This work provides evidence that high dopamine concentrations induce striatal mitochondrial dysfunction and increased generation of nitric oxide and hydrogen peroxide.