Cannabinoid CB1 receptors and ligands in vertebrate retina: localization and function of an endogenous signaling system.

摘要: CB1, a cannabinoid receptor enriched in neuronal tissue, was found high concentration retinas of rhesus monkey, mouse, rat, chick, goldfish, and tiger salamander by using subtype-specific polyclonal antibody. Immunolabeling detected the two synaptic layers retina, inner outer plexiform layers, all six species examined. In layer, CB1 located and/or on cone pedicles rod spherules. Labeling some amacrine cells ganglion cell axons except fish. addition, sparse labeling segments photoreceptors chick. Using GC/MS to detect possible endogenous cannabinoids, we 3 nmol 2-arachidonylglycerol per g but no anandamide detectable. Cannabinoid agonists induced dramatic reduction amplitude voltage-gated L-type calcium channel currents identified retinal bipolar cells. The presence distribution receptor, large amounts found, effects cannabinoids activity suggest substantive role for an signaling system physiology, perhaps vision general.