Cannabinoid receptor 1 (CB1) and Cannabinoid receptor 2 (CB2) (CB1 and CB2)

The cannabinoid receptors, Cannabinoid receptor 1 (CB1) and Cannabinoid receptor 2 (CB2), are Class A G protein-coupled receptors that function as the primary signaling components of the endocannabinoid system (UniProt P21554, P34972). CB1 is predominantly expressed in the central nervous system, particularly in the cortex, hippocampus, and cerebellum, where it modulates the release of neurotransmitters such as GABA and glutamate to regulate pain, appetite, and memory (StatPearls, Physiology, Cannabinoid Receptor). CB2 is primarily localized in the immune system and peripheral tissues, playing a significant role in modulating inflammatory responses and immune cell functions (PubMed, PMID: 26030169). These receptors are activated by endogenous ligands like anandamide and 2-arachidonoylglycerol, as well as exogenous compounds like THC and CBD (PubChem). Therapeutically, they are targeted for a variety of conditions including chronic pain, multiple sclerosis, and nausea, though CB1-targeted drugs often face challenges due to psychoactive side effects (NIH, The Endocannabinoid System).

Other names

CNR1CNR2CB1RCB2RCentral cannabinoid receptorPeripheral cannabinoid receptorCannabinoid receptor type 1Cannabinoid receptor type 2

Agonism, antagonism, and inverse agonism of G protein-coupled signaling pathways, primarily involving Gi/o proteins to inhibit adenylyl cyclase and modulate ion channels (StatPearls).