Oxygen dependency of cerebral CuA redox state during increased oxygen consumption produced by infusion of a mitochondrial uncoupler in newborn piglets.

Abstract

The mitochondrial uncoupler 2, 4-dinitrophenol (DNP) is a membrane soluble weak acid that is capable of transporting protons across the proton-impermeable inner mitochondrial membrane (Skulachev, 1998). This results in a reduction of the electrochemical gradient across the membrane and stimulation of flux through the electron transport chain, and thus oxygen consumption, without increasing cytosolic ATP hydrolysis. Uncouplers are used extensively in studies on isolated mitochondria to collapse the proton gradient and stimulate respiration (Rumsey et al., 1990), and to study the effects of the proton gradient on the redox state of the components of the electron transport chain (Morgan and Wikström, 1991). In this study, it was not the intention to collapse the mitochondrial proton gradient but to use low doses of DNP in order to stimulate oxygen consumption.