If you seek to use cannabis to treat various physical or psychological conditions, it may be useful to know how it works in the body. Cannabinoids like CBD and THC affect the body through the body’s Endocannabinoid System (ECS). Having a rudimentary understanding of this system and how it works may be beneficial in understanding which cannabinoid(s) to choose, and how they are affecting your body.
What is the Endocannabinoid System?
The Endocannabinoid System is an elaborate signaling system that enables cells to communicate using neurotransmitters called cannabinoids. The ECS plays an important role in regulating a number of different neural functions, including motor function, learning and memory, motivation, emotion, pain management, and addiction control. Cannabinoids come in two varieties: phytocannabinoids, and endocannabinoids. As the names imply, phytocannabinoids come from plants, and endocannabinoids are made inside the body. Both interact with the body’s two cannabinoid receptors, named CB1 and CB2.
Under most circumstances, our bodies produce and use endocannabinoids efficiently. However, when suffering from certain health conditions, an individual may benefit from taking phytocannabinoids. Although phytocannabinoids are found in other plants, they are mostly associated with cannabis. To understand how phytocannabinoids like CBD and THC affect the Endocannabinoid System, we first take a deeper look at the ECS and how it works.
How do Cannabinoid Receptors Work?
Each cannabinoid affects the cannabinoid receptors differently. THC, for example, acts as an agonist for both receptors, meaning that it connects with the receptors and produces reactions that catalyze various processes. Let’s examine these receptors one at a time.
CB1 Receptors
CB1 receptors are found abundantly in the central nervous system, and the brain in particular. They are also located in smaller numbers in peripheral nerve terminals, and in extra-neural sites such as the eye, testicles, vascular endothelium, and spleen. Because CB1 receptors are concentrated so heavily in the central nervous system, they play a prominent role in regulating metabolism, sleep, cellular respiration (in striated muscle tissue), as well as the brain’s limbic and reward actions. The limbic system regulates emotions and moods, and also drives (hunger, sex, care for offspring, etc.). The reward system provides the sensation of pleasure, and is responsible for the release of hormones such as dopamine or oxytocin during pleasurable experiences.
CB1 receptor agonists are those chemicals that bind to the receptor, acting as a catalyst for one or more actions. For example, THC is a CB1 agonist because it binds with the receptor, causing a number of effects in the body. For example, when THC binds with CB1 receptors in the brain’s reward system, it stimulates the release of dopamine, causing the user to experience a “high”.
CB1 receptor antagonists are those chemicals that block access to CB1 receptors, or otherwise dampen activity associated with their stimulation. CBD is a CB1 antagonist. Although CBD has a low binding affinity for CB1 receptors, it still seems to affect how those receptors respond to agonists. For example, CBD seems to modulate the effects produced by THC.
CB2 Receptors
CB2 receptors are located in white blood cells, and other immune system structures such as the spleen, tonsils, and thymus gland. They are also located in the brain, the gastrointestinal system, and the peripheral nervous system. In the gastrointestinal system, they play a role in regulating inflammatory intestinal response, such as with ulcerative colitis, Crohn's disease, and Inflammatory Bowel Syndrome (IBS). In the brain, CB2 receptors are associated with pain management.
In the immune system, the role of CB2 receptors is not fully understood at present, but current research suggests that CB2 agonists can suppress immune function. One way this occurs is by the inhibition of T-cell receptor signaling, which can result in a reduction of inflammation and pain. In particular, CB2 agonists may be helpful in reducing neuropathic pain (i.e. pain that arises from damage to nerve tissue).
How Does CBD Interact with the Endocannabinoid System?
With respect to both CB1 and CB2 receptors, CBD is an antagonist, not an agonist. That is, CBD does not bind efficiently to either receptor. However, that does mean that CBD produces the opposite effect of CB1 and CB2 agonists like THC. In many cases, CBD acts on these receptors seemingly by modulating the effects of their agonists, which can either mute or enhance their effects. For example, although CBD is a CB2 antagonist, it is highly effective for relieving pain.
CBD’s Role in Preserving Anandamide
Anandamide is a fatty acid neurotransmitter and an endocannabinoid. It binds with CB1 and CB2 receptors, catalyzing many of the processes associated with agonists of those receptors. It can reduce inflammation, relieve pain, regulate emotions and mood, and stimulate other activities associated with endocannabinoid receptor agonists.
Anandamide tends to last for a relatively short time in the body because it is regulated by Fatty Acid Amide Hydrolase (FAAH), an enzyme that breaks it down. However, CBD tends to slow the production of FAAH, thereby reducing the amount of it in the body. CBD thereby enables Anandamide to last longer in the body, and continue to its role as a receptor agonist. CBD plays a similar role with Fatty Acid Binding Protein (FABP), another enzyme whose role is to remove and metabolize Anandamide. By binding with FABP, it prevents FABP from doing its job, and thus the Anandamide is able to remain in the system longer.
A Summary of CBD’s Effects on the Body
Here are some of the known ways that CBD interacts with the body (and the resulting effects they produce):
- CBD is a weak antagonist of CB1 receptors
This may indicate how CBD plays a role in reducing pain.
- CBD is a strong negative allosteric modulator of the CB1 receptor
In addition to attenuating the psychotropic effects of THC, CBD may be linked to antipsychotic and sedative effects.
- CBD is a weak inverse agonist of the CB2 receptor
CBD reduces inflammation in several different areas of the body.
- CBD is an inhibitor of fatty acid amide hydrolase (FAAH)
CBD slows the metabolism of anandamide.
- CBD is an anandamide reuptake inhibitor
CBD keeps anandamide in the synapses by binding with FABP, thus preventing FABP from removing anandamide.
In Conclusion
Whereas THC acts on the CB1 and CB2 receptors directly, CBD’s impact is more subtle because it uses the body’s own endocannabinoids (e.g. anandamide) to stimulate the same processes. It produces many of the same positive reactions that THC does, but without the psychoactive effects. It reduces inflammation, relieves pain, regulates mood, relieves anxiety and depression, clears acne, relieves cancer symptoms, and can reduce the symptoms of many diseases and conditions. If you are interested in learning more about whether CBD is right for you, consult your primary care physician. You may be in a position to benefit from using this potent herbal compound.
*The statements made regarding these products have not been evaluated by the Food and Drug Administration. The efficacy of these products has not been confirmed by FDA-approved research. These products are not intended to diagnose, treat, cure or prevent any disease. All information presented here is not meant as a substitute for or alternative to information from health care practitioners. Please consult your health care professional about potential interactions or other possible complications before using any product. The Federal Food, Drug and Cosmetic Act requires this notice.