Cannabidiol (CBD) interacts with two dominant receptors (CB1 and CB2) of the endocannabinoid system (ECS). How it does so has been widely debated in the literature. The truth about CBD’s interaction with CB1 & CB2 is broken down in this article.
Generally, it is understood that CBD produces its effects through diverse molecular pathways. As it is, about 65 different pathways have been identified. When it comes to endocannabinoid receptors, CBD has a definite action on each of them. Through this action, some of CBD’s therapeutic effects are appreciated.
These receptors are predominantly found in the central nervous system. CBD acts as an allosteric modulator of CB1 receptors. An allosteric modulator changes the way the receptor works without actually activating it. This means that CBD can cause inhibitory effects on CB1 agonists (substances that increase the receptor’s activity), such as tetrahydrocannabinol (THC).
Since CBD does not occupy the same position as THC on the receptor, it cannot displace THC. However, it can “negate” some of its effects. These include improving memory loss associated with THC use and counteracting THC’s psychoactive effects .
Early on, it was believed that CBD binds directly to CB2 receptors. Crazy enough, it was also thought that there were no CB2 receptors in the central nervous system (the brain and spinal cord). What we now know is that these are myths.
While it’s true that there are CB2 receptors in the brain, most are found in the immune system. CBD acts as an inverse agonist at the CB2 receptor, meaning that it occupies the same position on the receptor and produces the opposite effect of the agonist. And–to make things a bit more complicated–its effects vary widely depending on its concentration.
In summary, CBD acts on cannabinoid receptors very differently. And, unlike THC, CBD also acts through many different non-cannabinoid receptor pathways to produce some of its therapeutic effects, explaining how it can be beneficial for so many different conditions. It’s also important to remember that CBD and THC are not the only cannabinoids in the plant and we are still learning how other compounds interact with this system, as well as terpenes.
As research continues to reveal complex interactions within in the ECS and beyond, stayed tuned as we keep on the beat of the evolving literature.
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