Figure 3: Melatonin inhibits H2O2-induced apoptosis in RPE cells. RPE cells were pretreated with different concentrations of melatonin (50 and 100 μM) for 48 h and exposed to 300 μM H2O2 for 24 h. Cell apoptosis was analyzed with MitoView dye. Apoptotic cells were stained red in mitochondria because of the mitochondrial membrane potential changing (scale bars are 200 μm).