Fig. 4. Reactive oxygen species (ROS) production in isolated mitochondria with succinate (Succ) as substrate. The effects of antimycin-A (A ) and ubiquinone (B ) on complex II-linked ROS production in the presence or absence (Con) of isoflurane (Iso) were analyzed after reverse electron flow induced-ROS was blocked by rotenone. Iso reduced reverse electron flow induced-ROS production in the absence of rotenone; however, Iso had no effect on the presence of rotenone, antimycin A, or ubiquinone. (C ) Summary of recordings. Data are presented as mean ± SD, n = 8/group. *P < 0.05 versus  corresponding Con; #P < 0.05 versus  the respective Con with Succ alone; §P < 0.05 versus  respective Con with rotenone.