Figure 1. Effect of blue light on metabolic activity. Metabolic activity of ARPE-19 cells measured by spectrophotometric detection of resazurin. Cells were unirradiated (white bars) or irradiated with either 1 mW/cm² (black bars) or 0.3 mW/cm² (red bars) for 3 h and 24 h. Bars represent mean±SD from n=5 separate experiments; The asterisk (*) indicates a p<0.05 (one-way ANOVA and Bonferroni test).