Figure 4. Brn3a-labeled retinal ganglion cells in flatmount retinas. Left: Brn3a signal (red); middle: 4’,6’-diamino-2-phenylindole (DAPI) signal (blue); right: superimposition of both images. The density of Brn3a+ RGCs in 6 and 12 weeks’ onset of diabetes and control mice are shown in the images (each visual field represents a 133 μm² area). All images were obtained at 40× magnification. Bar: 2 μm.