Effects of (+)-PTZ on retinas of WT mice. Representative photomicrographs of H&E-stained retinas of control (C57BL/6) mice (WT) that received (A) no (+)-PTZ injection or (B) 0.5 mg kg−1 (+)-PTZ injection twice weekly beginning at 8 weeks. Retinal appearance was similar between noninjected and injected WT mice. gcl, ganglion cell layer; ipl, inner plexiform layer; inl, inner nuclear layer; onl, outer nuclear layer; rpe, retinal pigment epithelial layer.