Figure 5.

Light micrographs depicting TFB-TBOA-dependent changes in pressure-loaded retinas. (a–c) The photomicrographs show retinas incubated with 20 nM TFB-TBOA at 10 (a), 35 (b), and 75 (c) mm Hg. (a) Axonal swelling (arrowheads) was induced in the NFL. The other retinal layers remained intact. (b) Degeneration of the thickened NFL, pyknosis of the GC nuclei (arrows), and bull's-eye formation (open arrows) in the INL were observed. (c) TFB-TBOA produced clear neurotoxicity with the development of bull's-eye neuronal profiles in the INL (open arrows) and severe spongiform dendritic swelling in the IPL. Swollen axons were found in the NFL. Note also the degeneration of GCs (arrows). The bull's-eye formation was found in the ONL. (d–f) Light micrographs of retinas incubated with 40 nM TFB-TBOA. (d) Axonal swelling (arrowheads) was induced by 40 nM TFB-TBOA at control pressure. The IPL became slightly edematous and the bull's-eye formation (open arrows) was found in the INL. (e, f) Retinas revealed clear neurotoxicity at 35 (e) and 75 (f) mm Hg. Marked axonal swelling in the NFL and degeneration of the GC (arrows) were found. Bull's-eye formation was also found in the ONL. (g–j) High magnification of the NFL and GCL in retinas incubated with 20 nM TFB-TBOA at 10 (g), 35 (h), and 75 (i) mm Hg. (g) The NFL became thickened by axonal swelling. The GCL, however, remained intact. (h) The thickened NFL and the GCs exhibit degeneration. (i) The thickened NFL showed degeneration with vacuole formation, while the GCL seemed intact. (j–l) High magnification of degeneration in the NFL and GCL. (i–l) Arrows: nuclear pyknosis of the GCs; open arrows: degenerated GCs. Scale bar: (a–f) 15 μm; (g–l) 7 μm.