Figure 7.

Immunohistochemical (a and b), western blot (c), and densitometry analysis (d) of 4HNE expression in normal and mutant retinas. Figure (a) is the full image of the retina and figure (b) shows the higher magnification images that focus on the photoreceptors. HNE labeling (red fluorescence) is present in the photoreceptor layer in normal and mutant retinas. Inner segment labeling increases in intensity at the time of active degeneration (E, H, K) and remains elevated until photoreceptor inner and outer segments are lost (L). DAPI (blue) nuclear stain. Scale bar: 20 μm; PR: Photoreceptor cells, ONL: outer nuclear layer; INL: inner nuclear layer. (b) western blot analysis of retinal samples taken in 7.7–13.6 weeks of age time window (see Table 1) with an antibody against 4HNE. Equal sample loading was determined with a GAPDH internal control. (c) Normalized 4HNE protein expression as fold increase over normal samples. 4HNE protein levels were increased in the 3 mutant groups and were significant in the xlpra2 and rcd1 retinas. The results are shown as the means ± SD. The significance of difference among groups was evaluated by a one-way ANOVA with a post hoc Tukey’s test. (One-way ANOVA, *P < 0.05).