Fig. 1. H₂O₂ induced oxidative damage to 661w cells.

a, b H₂O₂ decreased cell viability in a dose- and time-dependent manner. 661w cells were treated with different concentrations of H₂O₂ for 12 h in (a) (n = 5). 600 μmol/L H₂O₂ was used to treat 661w cells for different hours in (b) (n = 5). c 661w cells became round and shrunken with 600 μmol/L H₂O₂ treatment. The morphology changes were irreversible with 800 μmol/L H₂O₂ treatment. d H₂O₂ inhibited the activity of SOD and CAT, and decreased the level of GSH (n ≥ 4). e H₂O₂ increased cellular ROS generation. Data are shown as mean. Scale bar: 100 μm.