Analysis of the distribution pattern of microglial cells. (A-C) Drawings of microglial cell bodies labeled with immunoperoxidase in a representative area of the retina of a SD (A), untreated P23H (B) and tauroursodeoxycholic acid (TUDCA)-treated P23H rat (C). The localization of microglial cells in each of the retinal layers studied has been specified: GCL, red; IPL, green; OPL, blue. All images were collected from the medial area of the retina, in the superior quadrant. (D-F) Histograms of the nearest neighbors analysis in the OPL, IPL and GCL of SD (D), untreated P23H (E) and TUDCA-treated P23H rats (F). The solid line indicates the Gaussian function fitted to the data. The nearest neighbors analysis of a random pattern of the same density and standard deviation has been included for comparisons (dotted line). GCL, ganglion cell layer; IPL, inner plexiform layer; OPL, outer plexiform layer. Scale bar: 500 μm.