Receptors in the human body
Everything you need to know about the endocannabinoid system.
Endocannabinoids are cannabinoids created by the body to help regulate the various systems that keep it healthy. To truly understand CBD, it’s essential that we know what these cannabinoids do. Our bodies are composed of millions of cells which are constantly being replaced and repaired. Each cell is surrounded by a cell membrane. The human body also contains cannabinoid receptors – a class of proteins – which can be found inside the aforementioned membranes. Molecules can bind to these receptors and activate them, generating a biochemical or electric signal inside the cell.
The discovery of CB1 and CB2 cannabinoid receptors
In 1988, scientists first observed the interaction between the cannabinoid receptor type 1 (CB1) with cannabinoids like CBD and THC. CB1 receptors have been shown to be primarily expressed in the central nervous system, which has a crucial role in regulating pain responses, appetite, memory, emotions, sleep, coordination, and body temperature. In 1993, approximately five years later, a second cannabinoid receptor, CB2 (or cannabinoid receptor type 2) was first identified. CB2 receptors are primarily found on cells in the immune system. Studies have shown that these receptors may regulate the immune system and modulate immunological and inflammation responses
Cannabinoid receptors: where are they located and what do they do?
- Centraal nervous system
- Muscle tissue
- Sex organs
CB2 receptors are found in
- Immune system
- White blood cells
CB1 and CB2 receptors
- Immune system
- Bone marrow
Discovery of cannabinoids
After scientists discovered the different receptors, they were confronted with more questions than answers. Why would the human body even have receptors that bind to foreign substances? Shortly after the first cannabinoid was isolated from cannabis plant, scientists discovered that the human body produces similar molecules on its own. The prefix “endo” means “within”, which is why the cannabinoids produced within our bodies are known as “endocannabinoids”.
Agonist and antagonists
An agonist is a drug that activates certain receptors in the brain. All cells have many receptors on their cell surface, and each receptor has a unique “key” that can unlock it and send the signal. These receptors can be activated by different factors, including hormones and neurotransmitters. Most medications and supplements act by being either agonists or antagonists at these receptors that respond to these chemical messengers.
In contrast to antagonists, agonists bind to a receptor to stimulate its activity. The primary psychoactive component of cannabis, THC, binds to CB1 receptors, whereas its cousin, CBD doesn’t bind itself to these receptors. This could explain why CBD shows no psychoactive properties.
An inverse agonist is an agent that binds to the same receptor as an agonist but induces a response opposite to that agonist.
Unlike agonists, antagonists attach to a specific neurotransmitter receptor but do not result in the activation of said receptors. Antagonists are also referred to as “blockers”.
In addition to the well-known activity on CB1 and CB2 receptors, Studies examining the protective effects of CBD have shown that in additions to its activity on CB1 and CB2 receptors, CBD can also counteract the negative effects of THC. Furthermore, cannabinoids like CBD can influence a great deal of other different functions.
CBD inhibits the FAAH enzyme
While CBD works by activating serotonin, vanilloid, and adenosine receptors, it also inhibits the FAAH enzyme responsible for breaking down anandamide, a cannabinoid neurotransmitter that is part of the endocannabinoid system. Interestingly, anandamide is similar to THC. Like THC and many other cannabinoids, anandamide is an analgesic, and it is responsible for regulating other chemicals found in the brain, including serotonin.
Serotonin, also known as the happiness hormone, is a chemical that has a wide variety of functions in the human body. Its biological function is complex and multifaceted, modulating cognition, appetite, sleep, and mood. Low levels of serotonin are associated with depression and aggression. Serotonin binds at serotonin receptors (also called 5-HT receptors), which influence various biological and neurological processes such as addiction, anxiety, appetite, nausea, sleep, and pain responses.
When adenosine binds to the adenosine receptors, it induces sleep. At night, while we’re asleep, adenosine is broken down.
GPR55 receptors aid in controlling blood pressure and bone density.
What is the endocannabinoid system?
About 30 years ago, research led to the discovery of the human body’s endocannabinoid system. Our bodies naturally produce cannabinoids similar to the ones found in cannabis, referred to as endocannabinoids. Cannabinoids and endocannabinoids (i.e., cannabinoids found in the human body) closely resemble each other on a chemical level.
The endocannabinoid system (ECS) is a biological system composed of endocannabinoids that bind to cannabinoid receptors. The ECS can be seen as a biological regulatory system designed to keep the body in balance, as it regulates various bodily functions like:
- Pain response
- Immune response
How does the endocannabinoid system work?
There are two kinds of cannabinoids that can affect the body. The first group is known as the endocannabinoids, while the second group is known as exocannabinoids. “Exo” – or “exogenous” – means these cannabinoids are produced outside the body. Phyto cannabinoids such as THC and CBD are cannabinoids that occur naturally in the cannabis plant.
Research has shown that when THC, an exogenous cannabinoid, is consumed, it will interact with the CB1 and CB2 receptors in our body. The THC will activate the receptors in the same way that endocannabinoids do.
Unlike THC, CBD does not directly stimulate CB1 and CB2 receptors. Instead, it inhibits the FAAH enzyme, which breaks down anandamide, an endocannabinoid that is produced naturally by the brain. Anandamide is involved in regulating pain response and has been shown to modulate the transmission of serotonin.
Thus, endocannabinoids affect the function of many neurotransmitter systems. Research has shown that endocannabinoids and exogenous cannabinoids play a role in a number of areas in the body. To understand how the endocannabinoid system functions, you need a clear understanding of what cannabinoid receptors are and what they do.
The endocannabinoid system has become a prime target of research. To date, it has been implicated in the regulation of a variety of physiological processes, and research has shown that the endocannabinoid system is important for many physiological and pathological processes.
Bernard finds his passion in researching, creating and sharing content about medicinal cannabis and everything that relates to this mysterious and interesting plant. Besides the work he does as a microbiologist, Bernard is an inspiring blogger. He helps us to stay up-to-date about all trends and developments concerning CBD, medical cannabis, and much more. Do you have any questions? Feel free to contact us via the contact form or Bernard directly. Bernard can be reached directly by sending your message to [email protected]
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