Figure 3.

Effect of Hb on H₂O₂-induced alteration of mitochondrial membrane potential and caspase-3 activation in cultured astrocytes. Cells were co-incubated for 24 h with medium alone () or with H₂O₂ (50 µM) in the absence () or presence of graded concentrations of Hb (10⁻¹² to 10⁻⁶ M, ). (A) Mitochondrial transmembrane potential was assessed by using the JC-10 probe, and the ratio of fluorescence emissions 610/530 nm was measured as an index of mitochondrial activity. (B) Caspase 3 activity was measured by caspase substrate, Z-DEVDRhodamine 110, fluorescence. The results are expressed as percentage of controls. Data are means ±SEM of three independent experiments. ANOVA followed by Bonferroni’s test. **p < 0.01; ns, not statistically different from control cells. ^##p < 0.01; ^###p < 0.001; ns, not statistically different vs. H₂O₂-treated cells.