Changes in protein expression resulting from axotomy and lens injury. The proteins SPRR1A (a-c), MafK (d-f), Narp (g-i), and SOD-2 (j-l) were detected by immunofluorescence in normal rat RGCs (a, d, g, j) or in RGCs 4 d after axotomy without (b, e, h, k) or with lens injury (c, f, i, l). m-o, Representative colocalization study: cells were stained for SOD2 (n) and βIII-tubulin (m). The merged image (o) demonstrates that changes in SOD2 expression occur specifically in RGCs. Scale bar, 20 μm.