Figure 8. Changes in the expression level of protein kinase C alpha (PKCα) and synaptophysin after light exposure (ALE). Retinal cross sections reacted with antibodies to anti-PKCα and anti-synaptophysin. A-D: control animals, B, E, G, I: animals processed at 1 day ALE, C, F, H, J: animals processed 180 days ALE. B, C: PKCα signal, magnified in G, H. E, F: synaptophysin signal, magnified in I, J. Compared to control retinas, there is a decrease in the expression of these two proteins 1 day ALE and an increase 180 days ALE. K-L: Graphs showing the relative levels of fluorescent signal per labeled area of PKCα (K) and synaptophysin (L) in control and experimental retinas ALE. Asterisks: both indexes were statistically significant compared to control. # INL (K) and OPL (L) index was statistically significant compared to control, § IPL (K and L) index was statistically significant compared to control (Kruskal–Wallis test p≤0.05). Signal intensity level is expressed in arbitrary units, where 0 would be no fluorescence (black) and 65,335 (6×10⁴) would be the maximum fluorescence (white). See methods for further explanations. Abbreviations: IPL: inner plexiform layer. INL: inner nuclear layer. OPL: outer plexiform layer. Bar=100 µm.