In addition to acting on the brain, CBD influences many body processes. That’s due to the endocannabinoid system (ECS), which was discovered in the 1990s, after scientists started investigating why pot produces a high. Although much less well-known than the cardiovascular, reproductive, and respiratory systems, the ECS is critical. “The ECS helps us eat, sleep, relax, forget what we don’t need to remember, and protect our bodies from harm,” Marcu says. There are more ECS receptors in the brain than there are for opioids or serotonin, plus others in the intestines, liver, pancreas, ovaries, bone cells, and elsewhere.
Cannabidiol has low affinity for the cannabinoid CB1 and CB2 receptors, although it can act as an antagonist of CB1/CB2 agonists despite this low affinity. Cannabidiol may be an antagonist of GPR55, a G protein-coupled receptor and putative cannabinoid receptor that is expressed in the caudate nucleus and putamen in the brain. It also may act as an inverse agonist of GPR3, GPR6, and GPR12. CBD has been shown to act as a serotonin 5-HT1A receptor partial agonist. It is an allosteric modulator of the μ- and δ-opioid receptors as well. The pharmacological effects of CBD may involve PPARγ agonism and intracellular calcium release. cannabidiol