A Comparative Analysis of the Endocannabinoid System in the Retina of Mice, Tree Shrews, and Monkeys

Figure 2

CB2R system immunoreactivity pattern in the retina. Shown are retinal sections immunolabeled for CB2R ((a)–(d)), MAGL ((e)–(h)), and DAGLα ((i)–(l)) in mice, tree shrews, vervet, and macaque monkeys. The control staining, antibody preabsorption with the corresponding blocking peptide (BP), is also shown for CB2R, MAGL, and DAGLα in all species. Arrows point to low to moderate expression of CB2R, MAGL, and DAGLα in the retina all species and arrowheads to their high expression. The asterisks indicate expression of CB2R under the detection level in the inner retina of monkeys. ONL: outer nuclear layer; OPL: outer plexiform layer; INL: inner nuclear layer; IPL: inner plexiform layer; GCL: ganglion cell layer; NFL: nerve fiber layer. Scale bar = 75 μm.