Fig. 3.

Age and melatonin effects on the activity of complex I (a NADH dehydrogenase), complex II (b succinate dehydrogenase), complex III (c cytochrome bc₁ complex), and complex IV (d cytochrome c oxidase) of the electron transport chain in lung mitochondria from male and female SAMP8 mice. See legend of Fig. 1 for additional information. Results are expressed as a mean ± SEM value of six experiments measured in duplicate. *p < 0.05, **p < 0.01 and ***p < 0.001 compared with Veh5; ^###p < 0.001 compared with Veh10; ^‡p < 0.05 and ^‡‡‡p < 0.001 compared with the same group of males