Figure 1.

Blue light exposure reduced the number of intrinsically photoreceptive retinal ganglion cells (ipRGCs). Brown Norway rats were exposed to 12 hours of white light (1000 lx) and 12 hours of darkness for 10 days (control, 6 rats), 12 hours blue light (1000 lx), and 12 hours darkness for 10 days (long-term, 9 rats), and blue light (1000 lx) for 2 days (acute, 9 rats). Red fluorescence shows staining for melanopsin. (A) Control group, (B) long-term exposure group, and (C) acute-exposure group. (D) Circles indicate number of ipRGCs in one complete whole-mount retina from one rat; horizontal lines show mean. (E) Dots indicate differences between groups with regard to mean counts of ipRGCs in whole mount retinas; error bars show 95% confidence intervals for the differences. The P values and confidence intervals were calculated with Tukey's HSD test (R, version 4.0.4) after sensitivity analysis indicated that deviations from the assumptions of normality and homogenous variance would not affect conclusions about the statistical significance of differences.