The three G-protein-coupled cannabinoid receptor subtypes currently recognized are central (CB1), peripheral (CB2), and GPR55. The majority of CB1 receptors are found at central and peripheral nerve terminals. CB2 receptors are mainly found in immune cells and non-neuronal tissues where they regulate cytokine release and cell migration. According to recent reports, the CNS may also express CB2 receptors. Non-CB1/CB2 receptors known as GPR55 show affinity for endogenous, botanical, and synthetic cannabinoids. Anandamide and 2-arachidonylglycerol are examples of endogenous ligands for cannabinoid receptors.