A-I: Immunostaining for CHOP (A-B) and GFAP (D-E) immunostaining in the retina (A, B, D, E) and optic nerve (A′, B′, D′, E′). C, F: Bar graphs of CHOP (C, C′) and GFAP (F, F′) fluorescence intensities (Mean Gray Value) in the retina (C, F) and n0 to n3 optic nerve segments (C′, F′). G-I: Merged images and optic nerve segments (n0-n3). Nuclei in G and H were stained with DAPI (blue). Arrowheads indicate co-localization of CHOP and GFAP in the n0, n1 and n2 segments. I: CHOP distribution in unmyelinated versus myelinated optic nerve is shown by co-staining with myelin basic protein (MBP). *P < 0.05, **P < 0.01, ***P < 0.001 (unpaired t-test for retinas, two-way ANOVA with Sidaks's multiple comparisons test for optic nerve); #P < 0.05, ##P < 0.01, ###P < 0.001 (two-way ANOVA with Tukey's multiple comparisons test). Scale bar: 100 μm.