Figure 4. Time course of photoreceptor apoptosis in pigmented and nonpigmented retinas. Pigmented tg:zop:nfsB:EGFP zebrafish (A) or nonpigmented albino zebrafish (B) were subjected to intense light damage, and retinas were collected at the indicated time points and processed for terminal
deoxynucleotidyl dUTP nick end labeling (TUNEL) labeling. A: Rods were stained with anti-green fluorescent protein (GFP; green) antibody; nuclei were counterstained with TOPRO (blue).
Dorsal retinas are shown. Arrowheads indicate rods that appear condensed and lack OS. C: Quantification of TUNEL labeling for albino and pigmented zebrafish. Data represent mean±standard deviation (SD); *, p<0.005,
n = 3–7 retinas for each time point. D: Quantification of the ONL thickness for albino and pigmented zebrafish. All comparisons were made at 0 h. Data represent
mean±SD; *, p<0.05 using one-way analysis of variance with Tukey’s honest significant difference post hoc test; n = 5–7 retinas
for each time point. ONL, outer nuclear layer; INL, inner nuclear layer; GCL, ganglion cell layer; OS, outer segments. Scale
bar is 50 µm.