Rat Cannabinoid Receptor 1, Brain (CNR1) Protein

Background

Cannabinoid Receptor 1 (CNR1), commonly known as CB1, is one of the two primary receptors of the endocannabinoid system (ECS), a lipid signaling system that regulates homeostasis and diverse physiological processes. CB1 is predominantly expressed in the central nervous system (CNS), including regions like the hippocampus, cerebellum, and basal ganglia, where it modulates synaptic transmission and neuronal activity. CB1 interacts with endocannabinoids like anandamide (AEA) and 2-arachidonoylglycerol (2-AG), as well as exogenous cannabinoids like tetrahydrocannabinol (THC), the psychoactive compound in cannabis. Through this interaction, CB1 plays a key role in regulating pain perception, mood, appetite, memory, and motor control. In the periphery, CB1 expression in tissues such as the liver, adipose tissue, and pancreas contributes to energy metabolism, glucose homeostasis, and lipid storage, linking CB1 to obesity and metabolic disorders. Overactivation of CB1 signaling is associated with conditions like addiction, anxiety, and depression, as well as non-alcoholic fatty liver disease (NAFLD) and insulin resistance. CB1 antagonists, such as rimonabant, have been explored for treating obesity and metabolic syndrome, although their psychiatric side effects limit widespread use. The ECS, particularly CB1, continues to be a focus of intense research for developing safer therapeutics targeting pain, neurological disorders, and psychiatric conditions, including post-traumatic stress disorder (PTSD) and epilepsy.