Figure 3. Rimonabant attenuates H₂O₂-induced cytotoxicity and apoptosis. A: Inhibition of the H₂O₂-induced decrease in RPE cell viability by rimonabant. RPE cells were pretreated with rimonabant (0 to 5 μM) for 15 min before being exposed to H₂O₂ (200 μM) for 24 h, and cell viability was measured with the MTT assay. Values are the percentage of control (no H₂O₂, no rimonabant). *p<0.05 versus H₂O₂. B: RPE cells were pretreated with 1 μM ACEA for 15 min in the presence or absence of rimonabant (1 μM) before being exposed to H₂O₂ (200 μM) for 24 h. *p<0.05 versus H₂O₂. **p<0.01 versus rimonabant without ACEA. C: Flow cytometric analysis of cell death with DMSO, H₂O₂ (200 μM), rimonabant (1 μM), and rimonabant (1 μM) + H₂O₂ (200 μM). Cells were treated with different media as indicated for 24 h. Summary of the results showing a significant increase in apoptosis in RPE cells maintained in H₂O₂ (200 μM) compared with those maintained in vehicle. When the cells were incubated with rimonabant (1 μM), H₂O₂-induced apoptosis was significantly reduced. Treatment of RPE cells with rimonabant (1 μM) alone did not alter cell death. *p<0.05 versus vehicle H₂O₂ (n=4). The statistical test of A and B are one way ANOVA, n=4 per group. In the C, the test is two way ANOVA, n=4 per group.