FIG. 7.

Mitochondrial H₂O₂ elicits apoptosis in rotenone-exposed neuronal cells. The indicated cells were treated with (A and B) rotenone (0.5 and 1 μM) in the presence or absence of TTFA (10 μM) or antimycin A (50 μM) for 24 h, or (C, D, E, and F) pretreated with/without Mito-TEMPO (10 μM) for 1 h and then exposed to rotenone (0.5 and 1 μM) for 24 h, followed by (A, B, and C) H₂O₂ imaging using a peroxide-selective probe H₂DCFDA, (D) cell viability evaluation using the MTS assay, (E) cell apoptosis analysis using DAPI staining, or (F) Western blotting using the indicated antibodies. For (F), the blots were probed for β-tubulin as a loading control. Similar results were observed in at least three independent experiments. For (A), (B), (C), (D), and (E), all data were expressed as means ± SEM (n = 6). ^ap < .05, difference with control group; ^b p < .05, difference with 0.5 μM rotenone group; ^cp < .05, difference with 1 μM rotenone group.