What Are CB2 Receptors?

Green Shoppers Written by Green Shoppers
Updated on May 17, 2019

If you are reading this article, you have probably heard all about CBD already. The popular food supplement, formally known as cannabidiol, is a cannabinoid – it is one of the active compounds in the cannabis plant. There are thought to be perhaps one hundred cannabinoids found within the plant, other well-known ones including THC and CBG.

Cannabinoids are not the only important molecules, however. There are also terpenes, flavonoids which give flavour, and a number of other natural components.

The naturally occurring compounds in cannabis are able to affect our bodies in different ways. This is all because of the endocannabinoid system, a biological system tasked with maintaining homeostasis. Cannabinoids can target specific cannabinoid receptors found throughout this system in order to produce different effects.

Today, we will be taking a deeper look at the CB2 receptor and what it does, as well as why it is so important for your health.

The Endocannabinoid System & Receptors

Before we get into the ins and outs of the CB2 receptor, let’s talk a bit more about the endocannabinoid system (ECS). Throughout the whole day and night, your body is performing fundamental biological processes that you won’t even pay a second thought to. Without even having to think about it, the human body makes constant changes to ensure that we are safe, healthy, and alive.

A lot of this is down to the endocannabinoid system. Although only discovered recently in the grand scheme of things, the ECS is vital in keeping us alive. It regulates a number of functions, from temperature and sleep to mood, memory, pleasure, immunity, and more.

All of this is done through endocannabinoids and cannabinoid receptors. When the body needs to make a change, it creates molecules called endocannabinoids. These travel around the body and bind to matching cannabinoid receptors; scientifically, this is known as binding affinity. When the endocannabinoid binds to its respective receptor, neurons are fired around the body to pass along the message, and other parts of the body can adapt accordingly. This is a very efficient and important system, but sadly it is common to experience an endocannabinoid deficiency which can lead to problems.

Another key part of the system is enzymes. Once the endocannabinoids have completed their job, they are destroyed by the relevant enzymes to ensure they don’t remain in the body for an unnecessarily long time.

It is not just endocannabinoids like anandamide that can bind with cannabinoid receptors. In actual fact, plant cannabinoids can also bind to our cannabinoid receptors. THC, for example, has a binding affinity for the CB1 receptor; it is the interaction between the two which causes the psychoactive high triggered by consuming marijuana.

Research into the ECS is still fairly limited, but we know that there are at least two primary cannabinoid receptors, called CB1 and CB2. While they have some similarities, a primary difference between the two is that they are found in different locations.

CB2 Receptors: What They Do

The CB2 receptor was first discovered in the early 1990s. While the CB1 receptor is found mostly in the brain and central nervous system, the CB2 receptor lies primarily in cells in the immune system, gastrointestinal (GI) system, and the spleen.

The location of the CB2 receptors is what makes them so extremely important. This receptor has been strongly linked to the body’s inflammation response. When an injury occurs, it is natural and perfectly normal for the body to inflame the area as a means of protection. When inflammation is no longer needed, it is the role of the ECS and the CB2 receptor to reduce swelling and remove inflammation. Unfortunately, this does not always happen, and many medical conditions involve chronic and painful inflammation. In 2009, a study was published which suggested that the CB2 receptor is linked to a number of immune functional events due to its role in inflammation.

Furthermore, a 2014 study found that CB2 receptors also have a key role in modulating dopamine activity in the brain. This is despite the fact that CB2 receptors are not normally associated with the brain. In the study, the researchers found that cocaine-addicted mice administered themselves less cocaine when the CB2 receptor was activated, suggesting that damaged CB2 receptors could play a role in addiction disorders.

It is clear that the CB2 receptor is vital in maintaining our health, because it is intricately linked with a number of important functions.

Cannabinoids and the CB2 Receptor

In 2010, it was reported that anandamide has a poor binding affinity with the CB2 receptor; instead, this endocannabinoid prefers the CB1 receptor. It is actually sn-2-arachidonoylglycerol (2-AG) which binds better with the CB2 receptor.

Plant cannabinoids can also have an effect on the CB2 receptors. CBD, for example, can indirectly influence these receptors. When CBD is consumed, it may be able to stimulate the production of other endocannabinoids, helping the ECS to function properly. While CBD doesn’t bind with any receptors itself, it can help the ECS to stay afloat by assisting in endocannabinoid production.

This is why CBD is able to do things like relieve inflammation in sore muscles and the like. CBD doesn’t actually do this by itself – it’s more down to the proper functioning of the ECS and the CB2 receptor.

Final Thoughts on the CB2 Receptor

It is undeniable that more research is needed into the entire endocannabinoid system. We still understand very little about this system, and more studies need to be conducted into specific endocannabinoids and their receptors. It is quite unfortunate how little understood the CB2 receptor is, especially when it appears to play such a key role in the body.

What we do know is that the CB2 receptor is linked to inflammation and the immune system, and that keeping the ECS healthy is a good way to help the CB2 receptor to do its job properly. Taking CBD food supplements could be a good place to start, or applying a topical CBD rub to sore muscles – this may be able to reduce inflammation by targeting the CB2 receptor in localised areas.

Hopefully, we will see more exciting research regarding the endocannabinoid system in the future. The more we understand about this system, the more people can be helped with ailments relating to it.