The endocannabinoid system (ECS) consists of endocannabinoids, cannabinoid receptors, and enzymes that facilitate the synthesis and degradation of endocannabinoids. The effects of cannabinoids and endocannabinoids are mediated by two G protein-coupled receptors (GPCRs), namely CB1 and CB2. CB1 receptors are predominantly found in several brain regions, with lower quantities present throughout the central nervous system (CNS). These CB1 receptors primarily mediate the psychoactive effects of cannabinoids, leading to a sense of euphoria.
On the other hand, CB2 receptors are more prevalent in the CNS, as well as in numerous immune cells and neurons throughout the body. Both CB1 and CB2 receptors interact with inhibitory G proteins, and like other GPCRs, they are influenced by various pharmacological substances. The body’s response to specific cannabinoid receptor ligands is impacted by partial agonism, functional selectivity, and inverse agonism, all of which play critical roles.