The Endocannabinoid System and Phytocannabinoids
In the 1980’s and 90’s scientists discovered that human bodies naturally synthesize chemical transmitters called endocannabinoids and that these molecules have their receptors called cannabinoid receptors 1 and 2, CB1 and CB2. CB1 receptors are highly expressed in the central nervous system (CNS) brain cells called neurons and glia, but are also found in the periphery. CB2 receptors are associated with the immune system and are found in different organs in the body, including the spleen, kidney, liver, skin, etc. CB2 receptors are also present, but to a lesser extent than CB1 receptors in the CNS. Thus, the endocannabinoid system (ECS) consists of naturally synthesized (endogenously produced) endocannabinoids and cannabinoid CB1 and CB2 receptors (Mechoulam & Parker, 2013). Discovery of the endocannabinoid system has once again reignited our interest and perhaps even the trust in the inherent therapeutic properties of cannabis and its components.
The ECS is currently emerging as one of the vital systems that support the healthy functioning of the human body. As such, ‘endocannabinoid-deficiencies’ are thought to account for some of the underlying causes of neurological and immune dysfunctions (Smith & Wagner, 2014). Ongoing studies will shed further light on how the ECS changes with aging and how the ECS interacts with the multitude of other systems and chemicals in our bodies. In fact, the ECS is so vast and it interacts with so many body organs and systems, that we should start coining a new term – Endocannabinoid Systems (ECSs, in plural).*
Unlike endocannabinoids, cannabinoids that are synthesized by cannabis and other plants are called phytocannabinoids. In 1964, Israeli Professor Raphael Mechoulam discovered the most notorious phytocannabinoid, called THC or tetrahydrocannabinol. THC has been shown to bind CB1 receptors and induce an intoxicating effect called ‘the high’. Yet, in addition to its recreational intoxicating properties, THC has since been tested and shown to have a real therapeutic capacity. THC, however is only one of the 70 or more cannabinoids found in the cannabis plant. The second most prevalent phytocannabinoid is CBD, or cannabidiol. CBD is non-intoxicating and it is currently showing promising results in controlling seizures, anxiety, nausea, vomiting, and other dysfunctions (Mechoulam et al., 2014). Phytocannabinoids, like CBD and THC also can bind and interact with other, non-CB1/2 receptors in our bodies. This suggests that apart from THC, other non-intoxicating cannabinoids could have health benefiting properties through CB1/2 and other receptor and body system activation.
*Look out for Cannabinoid Insider blog that will explain why it may be appropriate to think of multiple ECSs or how ECS may play important roles in distinct body systems, such as respiration, digestion, central nervous system, etc.