The role of the endocannabinoid system

What is the endocannabinoid system and why does a human have one?

endokannabinoidijärjestelmän tarkoitus

“The endocannabinoid system is a system in the body that is one that promotes homeostasis, a balance in other functions.”

– Ethan Russo, MD –

Locations of the CB1 receptors

The cannabinoid CB1 receptors are primarily located on nerve cells in the brain, spinal cord, but they are also found in some peripheral organs and tissues such as the spleen, white blood cells, endocrine gland and parts of the reproductive, gastrointestinal and urinary tracts. (

Locations of the CB2 receptors

The cannabinoid receptor CB2 is not present in the central nervous system but mostly in tissues of the immune system. They have been found to be abundant throughout the body, such as in the intestines, spleen, liver, heart, kidneys, bones, blood vessels, lymphocytes, and reproductive organs. (S. Munro 1993)

The endocannabinoid system can be found at least:
  • From mammals
  • From birds
  • From lizards
  • From fish


Endo = Endogenic

The endocannabinoid system is so important that the U.S. Department of Health published a review that said the endocannabinoid system is associated with almost all human diseases 1. Indeed, the endocannabinoid system is one of the largest human receptor networks. It is one of the most important physiological systems in human health, and its receptors are found throughout the body, affecting almost all physiological processes in the body.  23

A breakthrough in finding the endocannabinoid system was not made until the early 1990s, when Lisa Matsuda and her colleagues at the National Mental Health Center succeeded in determining a THC-sensitive receptor in the rat brain. Thus, the first cannabinoid receptor CB1 was discovered. 4

Subsequently, in 1993, the next cannabinoid receptor was discovered – as part of the immune system and nervous system. CB2 receptors have been found to be abundant throughout the body, including the intestine, spleen, liver, heart, kidneys, skeleton, blood vessels, lymphocytes, and reproductive organs. 5

Cannabinoids, terpenes and flavonoids naturally occurring in hemp act together and individually, directly or indirectly, to balance the endocannabinoid system. 6


The basic functions of the ECS: “relax, eat, sleep, forget and protect.”

The endocannabinoid system (ECS) is like a bridge between body and mind. By understanding it, one can begin to see the mechanism that affects brain function, physical health, and the treatment of disease. 2

In 1998, Professor Di Marzo summed up the basic functions of the endocannabinoid system with the words “Relax, eat, sleep, forget and protect”. (23)

The endocannabinoid system is a network of receptors known at least in mammals, birds, lizards and fish. 7. Research on endocannabinoids is young and constantly evolving. New and surprising discoveries appear regularly. Findings on the functions and evolution of the endocannabinoid system reveal new insights into how cannabinoids affect health and disease management. 8, s. 53

Cannabinoids act on the body by binding to the molecular receptors encoded by our genes. These cannabinoid-capturing receptors are proteins found on the surfaces of our cell membranes. Because cannabinoids bind to receptors in the form of cannabinoids, they are called cannabinoid receptors. 8, s. 53

How does the endocannabinoidsystem system work?

The endocannabinoid system acts holistically in the body in a number of different ways. It is involved in the regulation of pain, appetite, metabolism, emotional states, memory, and sleep-wake rhythm. The endocannabinoid system includes CB1 and CB2 cannabinoid receptors, as well as other already known and as yet unknown receptors. It is also associated with the endorphin system, as well as the release of various neurotransmitters in neurons. In addition, there are so-called endocannabinoids in the body, the best known of which are anandamide and 2-AG. 8, s. 54

Where are CB1 and CB2 receptors located in the body?

The CB1 and CB2 receptors of the endocannabinoid system are found in almost every part of the body. CB1 receptors are particularly found in the brain and central nervous system.

G-protein receptors are the broadest class of receptors in the body – there are more than 1,000 different people in humans. Indeed, 30-50% of all modern drugs act on these receptors. (9  103). The most common g-protein receptor in the brain is the cannabinoid receptor CB1, which is about 10 times the amount of other g-protein receptors.10.

CB2 receptors are found most in the immune system. Different receptors and related cannabinoids and the like have different functions and effects in the body. 8, s. 54.

Indeed, the endocannabinoid system affects the body in a multidimensional way by regulating the central nervous system and the immune system. The functioning of the system can both accelerate and slow down physiological functions. The psychological effects of cannabinoids in hemp and the body are due to CB1 receptors. The effects of CB2 receptors are even more physiological. (118)


How can the endocannabinoid system be affected?

The endocannabinoid system can be affected by the addition of exogenous, i.e., external, cannabinoids associated with their receiving cannabinoid receptors, or by the activation of endocannabinoid cleavage enzymes. 12. In addition, the balance of endocannabinoids can be affected by exercise. 13.

Based on the latest research, Ethan Russo, a neurologist and research and development director at the International Cannabis and Cannabinoid Institute (ICCI), and many other researchers in the field theorized that the endocannabinoid system is designed to maintain balance in the body’s systems by slowing down and accelerating processes as needed. 14. According to him, many diseases are caused by deficiencies in the endocannabinoid system. 15.

Cannabinoid receptors and cannabinoids acting on it


The cannabinoid receptor CB1 was discovered in 1990. 4


The second cannabinoid receptor, CB2, was discovered shortly after the first in 1993. 5

CBN, cannabinol

Researchers discovered cannabinol, or CBN, as the first cannabinoid in 1896. 16

CBD, cannabidiol

Cannabidiol, or CBD, was discovered in 1970. 17


THC, or tetrahydrocannabinol, was discovered by the ancestor of cannabinoid researchers, Raphael Mechoulam, along with his research team. THC is one of the most important cannabinoids for the discovery of the entire endocannabinoid system, as it also led to the discovery of cannabinoid receptors and endocannabinoids. 18. Regular use of THC can cause imbalances in the endocannabinoid system. 21


Raphael Mechoulam discovered the first intracorporeal cannabinoid with his research team. 19


Another endocannabinoid, 2-AG, was also discovered shortly after anandamide under the direction of Raphael Mechoulam 20


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  3. Russo, E.  Introduction to the Endocannabinoid System. PHYTECS.
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  5. Sean Munro, Kerrie L. Thomas & Muna Abu-Shaar. 1993. Molecular characterization of a peripheral receptor for cannabinoids. Nature.  
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