Stimulation and inhibition of muscarinic signaling disrupts the patterning of cholinergic amacrine cells. Panels a and b are representative fields of view from the GCL of retinas treated with saline (a) or atropine (b). Whole-mount preparations of the retina were labeled with antibodies to ChAT and images were obtained by using confocal microscopy. The calibration bar (50 μm) in panel b applies to panels a and b. Panels c-e are dot-plots that were obtained by marking the center of individual cholinergic cells in the GCL of retinas treated with saline (c), atropine (d) or carbachol (e). Panel f is a histrogram of the mean regularity indices measured from cells of 3 different retinas that were treated with saline, atropine or carbachol. The significance of difference was assayed by using ANOVA (p = 0.0017) and a post-hoc Student's t-test (2 tailed, equal variance; *p = 0.00016, **p < 0.0013).