The endocannabinoid system (ECS) is named for the plant that led to its discovery, but evolutionary evidence shows us that it had been a central component of human physiology for hundreds of millions of years before cannabis existed. Despite early evolution of the ECS and its central role in body function, the ECS was not discovered until 1992. Initially, cannabis derived cannabinoids were discovered in 1964 via the isolation of THC. CBD was soon after isolated as well. Investigating THC’s effect on the body led to the discovery of the ECS. 

The ECS is made up of three main components: cannabinoid receptors, endogenous cannabinoids, and enzymes. The first cannabinoid receptor was found in 1988 and coined the CB1 receptor. A second receptor, the CB2, was found soon after. Cannabinoid receptors are found on the cell surface and influence how messages are sent, received, and processed by cells in order to maintain a homeostatic (healthy/balanced) state. CB1 receptors are most densely concentrated in the central nervous system (CNS), especially in areas of nociception (pain perception), short-term memory, and basal ganglia, but they are also found in the peripheral nerves, uterus, testes, bones, and most other body tissues. Due to their location in the CNS, CB1 receptors are responsible for the psychoactive effects of THC. CB2 receptors, in contrast, are mostly found in the periphery, often in conjunction with immune cells. They may also appear in the CNS, particularly under conditions of inflammation in association with microcytes. CB1 and CB2 are the most common ECS receptors, although cannabinoids can bind to at least another eight receptors that are not part of the mainstream conception of the ECS.

To read more about the endocannabinoid system purchase Cannabis Primer: An Introduction to Cannabis for Consumers, Producers, Providers, Policy Makers, and Health Professionals