What is CBD?

How CBD works

CBD's actions within the brain and body are quite complicated. It's very likely that the beneficial effects of CBD operate through diverse biological pathways, rather than by a single action. More research is needed to fully understand the mechanisms by which CBD relieves ailments such as seizures.

CBD directly interacts with several proteins in the body and central nervous system, a few of which are components of the endocannabinoid system (ECS). CBD has an affinity for both the CB1 and CB2 cannabinoid receptors. Our bodies have several other receptor proteins that participate in the endocannabinoid system, such as GPR3, GPR6, TRPV1, and TRPV2, for example. CBD binds to all of these, and its possible anti-inflammatory and pain-relieving effects may occur through these pathways.

Serotonin Receptors

Jose Alexandre Crippa and his colleagues at the University of San Paulo in Brazil and King’s College in London have conducted pioneering research into CBD and the neural correlates of anxiety. At high concentrations, CBD directly activates the 5-HT1A (hydroxytryptamine) serotonin receptor, thereby conferring an anti-anxiety effect. This G-coupled protein receptor is implicated in a range of biological and neurological processes, including (but not limited to) anxiety, addiction, appetite, sleep, pain perception, nausea, and vomiting.

5-HT1A is a member of the family of 5-HT receptors, which are activated by the neurotransmitter serotonin. Found in both the central and peripheral nervous systems, 5-HT receptors trigger various intracellular cascades of chemical messages to produce either an excitatory or inhibitory response, depending on the chemical context of the message.

CBDA [Cannabidiolic acid], the raw, unheated version of CBD that is present in the cannabis plant, also has a strong affinity for the 5-HT1A receptor (even more so than CBD). Preclinical studies indicate that CBDA is a potent anti-emetic, stronger than either CBD or THC, which also have anti-nausea properties.

Vanilloid Receptors

CBD directly interacts with various ion channels to confer a therapeutic effect. CBD, for example, binds to TRPV1 receptors, which also function as ion channels. TRPV1 is known to mediate pain perception, inflammation and body temperature.

TRPV is the technical abbreviation for “transient receptor potential cation channel subfamily TRPV1 is one of several dozen TRP (pronounced “trip”) receptor variants or subfamilies that mediate the effects of a wide range of medicinal herbs.

Scientists also refer to TRPV1 as a “vanilloid receptor,” named after the flavorful vanilla bean. Vanilla contains eugenol, an essential oil that has antiseptic and analgesic properties; it also helps to unclog blood vessels. Historically, the vanilla bean has been used as a folk cure for headaches. CBD binds to TRPV1, which can influence pain perception.

Capsaicin—the pungent compound in hot chili peppers—activates the TRPV1 receptor. Anandamide, the endogenous cannabinoid, is also a TRPV1 agonist.

GPR55—orphan receptors

Whereas cannabidiol directly activates the 5-HT1A serotonin receptor and several TRPV ion channels, some studies indicate that CBD functions as an antagonist that blocks, or deactivates, another G protein-coupled receptor known as GPR55.

GPR55 has been dubbed an “orphan receptor” because scientists are still not sure if it belongs to a larger family of receptors. GPR55 is widely expressed in the brain, especially in the cerebellum. It is involved in modulating blood pressure and bone density, among other physiological processes.

GPR55 promotes osteoclast cell function, which facilitates bone reabsorption. Overactive GPR55 receptor signalling is associated with osteoporosis.