Figure 3
From: Assembly of the outer retina in the absence of GABA synthesis in horizontal cells
Pattern of GAD67 expression in αPax6-Cre:Gad1lox/lox(mutant) retina. (a) The spatial distribution of Cre recombinase expression across the retina parallels the pattern of GFP expression in amacrine cells. Cre expression is present in all cells of the embryonic retina, but several days after birth becomes restricted to subpopulations of amacrine cells [63]. At P8, GFP is expressed by relatively few cells in central retina (box, b) and a larger number of amacrine cells in the peripheral retina (box, c). Staining for GAD67 follows an inverse pattern in this mutant retina. (b) Numerous GAD67-immunopositive amacrine cells near the center of the mutant retina. hc, horizontal cells; ac, amacrine cells. (c) GAD67 immunoreactivity is largely absent in the retinal periphery of the mutant retina. Immunofluorescence in this image (arrow) marks blood vessels. There is no GAD67 immunoreactivity at retinal depths where amacrine cells (ac) and horizontal cells (hc) are located. (d) In the wild-type region of a P3 mutant retina, GAD67-immunopositive horizontal cells (hc) also contain GABA. In knockout regions of this retina, GAD67 and GABA immunolabeling are absent. Arrow (mutant) indicates immunoreactivity in some blood vessels.