Cannabinoids and the endocannabinoid system, a brief history explained
By Richard Hamilton – The Grower’s Guide
Most of us are familiar with cannabinoids, the chemicals that give the cannabis plant its medical and recreational properties. THC, CBD are the most prevalent and understood of these chemicals but in total there are over 100 cannabinoids, all of which interact with different receptors in the body to produce a varied and wide range of effects from the classic THC “high” to the anti-inflammatory and neuroprotective properties from CBD.
Do you however know what an endocannabinoid is? Or what the endocannabinoid system is? Here, we will break down the history of how both cannabinoids and the endocannabinoid system were discovered, the undisputable science that lies behind them and the therapeutic effects that it shows both THC and CBD to be capable of delivering. As debate about the use of cannabis for health and wellbeing continues, this information could not be more relevant.
Cannabis and hemp has been used medicinally and recreationally for over 4000 years however it was only at the end of the 19th century that anyone managed to isolate its active element. Researchers at Cambridge University distilled an Indian Charas, (hashish form of cannabis from the plant’s resin) and extracted an oil that induced marijuana like effects. They isolated a crystalline compound from this oil and named it “cannabinol” the first cannabinoid had been discovered and extracted in pure form.
The structure of Cannabinol was more clearly defined in the 1930’s in the United States, when CBD (cannabidiol) was also successfully isolated from the cannabis plant. It was not then until the 1960’s, when scientific technology advanced enough, that anyone managed to isolate and identify the active compound that produced the psychoactive effects of cannabis, THC.
“It comes as no surprise knowing what we know now that the receptors are largely concentrated in the regions of the brain responsible for mental and physiological processes.”
Once THC had been isolated it was then synthesized and made available for research, since when there have been literally thousands of research papers describing its effects. At first it was assumed that due to its seemingly soluble chemistry that THC would act on the body non-specifically, but this was not so.
It was as late as 1988 when a US funded government study at St Louis University discovered a specific cannabinoid receptor in the brain of rats. The receptor consisted of specialized protein molecules embedded in cell membranes and responded to compounds in the marijuana resin. It was named “cannabinoid-1 receptor” (CB1).
Shortly after this, researchers were able to map the exact location of many more cannabinoid receptors in the brain. It’s unbelievable that this breakthrough research was only completed and presented to the general science community as late as 1990, which is within most of our lifetimes!! It comes as no surprise knowing what we know now that the receptors are largely concentrated in the regions of the brain responsible for mental and physiological processes. Cannabinoid receptors work by acting as tiny sensors that pick up biochemical cues flowing through fluids surrounding each cell.
A second receptor “CB2” was then found to reside right across the body, in the immune system, the nervous system, the gut, spleen, liver, heart, kidneys, bones, blood vessels, lymph cells, endocrine glands and even the reproductive organs.
With these receptors located all over the body and brain it is easy to understand why cannabis is such a versatile medicine with CB1 helping to regulate psychoactivity and CB2 assisting in immune response.
Further research in 1992 led to the findings of a natural THC like compound that existed within our bodies in the form of naturally occurring neurotransmitters that attached to the same brain cell receptors as THC. These neurotransmitters would become known as endocannabinoids. A neurotransmitter acts as the body’s chemical messenger, they are molecules used by the nervous system to transmit messages from neurons to muscles.
In 1995 another of these neurotransmitters was discovered that was attracted to both the CB1 and CB2 receptors. By tracing the metabolic pathways of THC a previously unknown molecular signalling system was discovered. This was involved in regulating many biological functions and it was named “the endocannabinoid system” after the plant that led to its discovery.
It is believed that the endocannabinoid system is present in every animal except for insects and has evolved over the last 600 million years, before cannabis existed in any form and whilst most life forms were still a ball of cells. Its evolutionary history indicates that the endocannabinoid system must have a very important role to play in the physiology of animals and humans.
CB1 and CB2 receptors only respond to 3 types of “on switches” endocannabinoids within the body, phyto-cannabinoids from the resin on buds and leaves on cannabis plant and synthetic cannabinoids. So out of those, only 2 are natural and only 1 exists outside of our body. You could say therefore that cannabis was literally MADE for our bodies, the perfect fit for our health, well being and survival.
Endocannabinoids and their receptors continue to be researched today, paving the way for new treatment strategies for conditions including Cancer, diabetes, neuralgia, arthritis, osteoporosis, Alzheimers and depression. It has been proven that cannabinoid compounds can affect the progression of disease and halt or slow down symptoms, whilst other experiments proved that CB-receptor signalling could help adjust pain, inflammation, appetite, digestion and sleep cycles. They also work as modulators for other mood altering neurotransmitters such as serotonin, dopamine and glutamate.
“The functions of most cannabinoids still remain largely undiscovered and it is amazing to think what we could find out about them with continued scientific research”
Cannabinoid receptors are amazing, unlike any other neurotransmitter they perform “retrograde signalling” which is a form of communication that actually inhibits and reduces your bodies responses, calming and soothing the mind and body. For example they can lower blood pressure, relax muscles and nerves and basically chill the body out. They are like the controller of all the other neurotransmitters, telling them to back off and cool down when they are ramping up too much. They restore the balance and bring us peace.
Cannabis is a unique and natural medicine that tunes into how our bodies work biologically on the deepest of levels. It is because of this humble plant that science has discovered how brain cells and nerves talk to each other! The functions of most cannabinoids still remain largely undiscovered and it is amazing to think what we could find out about them with continued scientific research. The psychoactive compound THC is without doubt the most well known cannabinoid, but arguably it is the other known compound CBD that shows the most promise in the treatment of pain, anxiety and epilepsy. Across all stages of life from birth to death the cannabinoids and the endocannabinoid system guides and protect.
With such huge social stigma and general misunderstandings attached to cannabis, and with such undeniable evidence of its versatility as a natural remedy at the same time, it is easy to see why cannabis is without doubt the Worlds most popular illegal substance.
By Rich Hamilton – The Grower’s Guide
this article was published in the June issue of the Hemp & CBD Mag – Read the full issue here