FIGURE 7.

Decylubiquinone increases complex I/III inhibition threshold in synaptosomes, when titrated with myxothiazol. Rat brain synaptosomes were incubated with a series of concentrations of myxothiazol (0–1 μm) in the absence and presence of 50 μm decylubiquinone in Krebs buffer in an oxygen electrode at 37 °C. Rates of oxygen consumption and corresponding complex I/III activity were determined and expressed as percentages of their controls and used to generate the complex I/III inhibition threshold curves in the absence (●) and presence (○) of decylubiquinone. The control rates of complex I/III activity in the absence and presence of decylubiquinone were 44.2 ± 4.8 nmol/min/mg and 73.8 ± 8.25 nmol/min/mg, respectively. Experiments were performed on five individual preparations, and results are expressed as mean ± S.E. (error bars).