Receptor for endocannabinoid N-arachidonyl glycine (NAGly). However, conflicting results about the role of NAGly as an agonist are reported. Can also be activated by plant-derived and synthetic cannabinoid agonists. The activity of this receptor is mediated by G proteins which inhibit adenylyl cyclase. May contribute to regulation of the immune system. Is required for normal homeostasis of CD8+ subsets of intraepithelial lymphocytes (IELs) (CD8alphaalpha and CD8alphabeta IELs) in small intstine by supporting preferential migration of CD8 alphaalpha T-cells to intraepithelial compartment over lamina propria compartment, and by mediating their reconstitution into small intestine after bone marrow transplant. Plays a role in hypotensive responses, mediating reduction in intraocular and blood pressure. Mediates NAGly-induced process of reorganization of actin filaments and induction of acrosomal exocytosis. Belongs to the G-protein coupled receptor 1 family.