CBD exerts its actions through a variety of pathways. One site of action is the endocannabinoid system, a system of receptors found in the brain, central and peripheral nervous systems, fat, muscle, and immune cells. Naturally occurring substances called “endocannabinoids” and the cannabinoids found in marijuana are major effectors on this system.
THC is a strong activator of the endocannabinoid system while CBD has a weaker activation impact on the system, but its mechanism of action is more complicated. Both THC and CBD bind to the endocannabinoid receptor called CB1. By weakly binding CB1 receptor, CBD is thought to inhibit the release of glutamate, an excitatory neurotransmitter7. This is important because the inhibitory actions of the CB1 receptor play a role in maintaining normal brain activity – CB1 receptors protect the brain against seizures8.
Through its interactions with the endocannabinoid system, CBD may counteract many of the psychological and physiological effects of THC9. Additionally, CBD increases levels of an endocannabinoid called anandamine, which creates anti-inflammatory effects through its activation of cannabinoid receptors10.
Another biochemical target of CBD is the transient receptor potential (“TRP”) class of channels. These channels affect the levels of calcium within the cell. The action of CBD at these receptors can increase calcium levels in a number of different types of cells11.
CBD also increases signaling of the 5HT-1A serotonin receptor12. Serotonin is a chemical found in the body that regulates mood balance. Serotonin system dysfunction is associated with a variety of disorders, including depression. Many antidepressants work by increasing serotonin levels in the brain13. The actions of CBD at serotonin receptors have been associated with decreasing anxiety and protecting brain cells from death.
CBD has been shown to protect the brain from damage due to oxidative stress, decreased brain inflammation, and increased levels of a neurotransmitter called adenosine, a molecule important for energy creation and sleep regulation. Each of these effects has the potential to offer therapeutic benefits14.