Figure 7.

Changes in microglial cells and GFAP expression with age in RCS rats. Photomicrographs from the mid-dorsal retina of representative cross sections of P23H-1 rats of different ages from P10 (upper row) to P60 (lower row) showing immunolabeled microglial cells (Iba1⁺, green, A–E), astrocytes and Muller cells (GFAP⁺, red, A'–E') and DAPI-counterstaining (blue; A'–E'). At P21 (B,B') microglial cells migrate toward the outer retinal layers (red arrows), but the expression of GFAP and the thickness of the ONL remain unchanged. At P45 there are more microglial cells in the retina and they enter the OS layer, there is overexpression of GFAP and a decrease in thickness of the ONL (D,D'). At P45 the thickness of the ONL has decreased further, there is more microglia in the OS layer and more GFAP expression in Müller cells (E,E'). Scale bar = 100 μm.