The endogenous cannabinoid system, named after the plant that led to its discovery, is perhaps the most important physiologic system involved in establishing and maintaining human health. Endocannabinoids and their receptors are found throughout the body: in the brain, organs, connective tissues, glands, and immune cells. In each tissue, the cannabinoid system performs different tasks, but the goal is always the same: homeostasis, in other words, the maintenance of a stable internal environment despite fluctuations in the external environment.
Scientists discovered that there are receptors in the human body that responds positively to chemical compounds (cannabinoids). Cannabinoid receptors are present throughout the body, embedded in cell membranes. When cannabinoid receptors are stimulated, a variety of physiologic processes ensue. Researchers have identified two cannabinoid receptor systems:
Cannabinoids interact with the body’s endocannabinoid system, or the ECS. The endocannabinoid system helps to maintain equilibrium in bodily processes such as sleep, memory, mood, appetite, and pain.
In the simplest terms, the ECS is a signaling network that extends throughout the body. This extensive network is made up of cannabinoid receptors, endocannabinoids—cannabinoids that the body produces—and enzymes that help to create and break down endocannabinoids after they’ve been used.
Cannabinoid receptors form a fundamental part of this system. There are two known types in the body: CB1 and CB2. These receptors are located in the brain, spinal cord, organs like the gastrointestinal tract, and peripheral parts of the body. Endocannabinoids can stimulate these cannabinoid receptors, provoking responses such as feelings of sleepiness, relaxation, or hunger.
CB1, predominantly present in the nervous system, connective tissues, gonads, glands, and organs; and
CB2, is predominantly found in the immune system and its associated structures.
Cannabinoids promote homeostasis at every level of biological life
From the sub-cellular to the organism, and perhaps to the community and beyond. Here’s one example: autophagy, a process in which a cell sequesters part of its contents to be self-digested and recycled, is mediated by the cannabinoid system.
While this process keeps normal cells alive, allowing them to maintain a balance between the synthesis, degradation, and subsequent recycling of cellular products, it has a deadly effect on malignant tumour cells, causing them to consume themselves in a programmed cellular suicide. The death of cancer cells, of course, promotes homeostasis and survival at the level of the entire organism.
Cannabinoid receptors are present throughout the body, embedded in cell membranes, and are believed to be more numerous than any other receptor system. When cannabinoid receptors are stimulated, a variety of physiologic processes ensue. Researchers have identified two cannabinoid receptors: CB1, predominantly present in the nervous system, connective tissues, gonads, glands, and organs; and CB2, predominantly found in the immune system and its associated structures.
Many tissues contain both CB1 and CB2 receptors, each linked to a different action. Researchers speculate there may be a third cannabinoid receptor waiting to be discovered. Endocannabinoids are the substances our bodies naturally make to stimulate these receptors. The two most well understood of these molecules are called anandamide and 2-arachi-donoylglycerol (2-AG). They are synthesised on-demand from cell membrane arachidonic acid derivatives, have a local effect and short half-life before being degraded by the enzymes fatty acid amide hydrolase (FAAH) and mono-acylglycerol lipase (MAGL).
Phytocannabinoids are plant substances that stimulate cannabinoid receptors. Delta-9-tetrahydrocannabinol, or THC, is the most psychoactive and certainly the most famous of these substances, but other cannabinoids such as cannabidiol (CBD) and cannabinol (CBN) are gaining the interest of researchers due to a variety of healing properties. Most phytocannabinoids have been isolated from cannabis Sativa, but other medical herbs have been found to also contain non-psychoactive cannabinoids.
Laboratories can also produce cannabinoids. Synthetic THC, marketed as dronabinol (Marinol), and nabilone (Cesamet), a THC analogue, are both approved drugs for the treatment of severe nausea and wasting syndrome. Many other synthetic cannabinoids are used in animal research, and some have potency up to 600 times that of THC.