Ablation of GluN2 subunits in the retinas of mutant mice. (A) Immunostaining of calretinin (green) in ROSA-tdTomato/c-kit-Cre mice. Overlapping of tdTomato fluorescence (red) and calretinin indicated that Cre-mediated recombination occurs in RGCs (arrows) and amacrine cells (arrowheads). Enlarged image of the GCL in the upper panel was shown. Scale bar, 20 μm (upper) and 10 μm (lower). (B) Immunohistochemical analysis of GluN2B in GluN2Bf/f and GluN2B conditional knockout mice (GluN2Bf/f/c-kit-Cre). Scale bar, 20 μm. (C-F) Western blot analysis of retinas from WT and GluN2 mutant mice with respective antibodies (GluN2A, GluN2B, GluN2C, GluN2D and β-actin). For GluN2B, control (con) represents GluN2Bf/f mice. Asterisks indicate the GluN2B protein bands. Each lane was loaded with 30 μg of proteins. GCL, ganglion cell layer; IPL, inner plexiform layer; INL, inner nuclear layer; ONL, outer nuclear layer.