Cannabinoids and their receptors are in nature present throughout the entire human body. Because of this, scientists believe that the compounds provides various physiological functions, mostly in the brain and also in the spinal cord, both of which hold numerous CB1 receptors. What happens is that when cannabinoids unite with these receptors, they start a chain reaction that slows down the diffusion of nerve impulses between cells. This is not always what happens in other nerve cells, though. CB1 receptors are ordered in such a manner that they hasten the release of messages along the neural pathways.
CB1 receptors are largely found in parts of the brain that control memory, movement, complex thought, and response to stress which are functions that are surprisingly not affected by marijuana. Researches show that the body’s natural cannabinoids play an innate role in all of the processes involved, including the control of nausea and vomiting and pain perception.
It has been observed that under the influence of marijuana, people’s bodies do tend to be affected. They often have a hard time holding their hands steady. Laboratory experiments showed their activity to be restrained. Since CB1 receptors are concentrated mostly in regions of the brain that are responsible for movement coordination, it is probable that these receptors account for the various effects of cannabinoids on activity and movement.
Because cannabinoids influence movement through different routes, they are encouraging as a probable source of new medicines that could treat movement disorders. Moreover, CB1 receptors are reasonably plentiful in areas of the spinal cord and brain controlling pain perception. In laboratory experiments designed to measure animals’ responses to escapable and moderate pain, animals given cannabinoids responded in almost the same way as those animals given pain-killing opiate drugs like morphine.
Aside from that, cannabinoids also seem to play a role in pain transmission down peripheral nerves. These nerves are responsible for detecting sensations in the entire human body and relaying messages to the brain through the spinal cord. These peripheral nerves exhibit both CB1 and CB2 receptors on their surfaces and studies of animals indicate that cannabinoids connect to every receptor type and are able to block nerve pain. The results imply that a fusion of cannabinoids could actually enhance the effect of alleviating peripheral pains in humans.
A lot of people have reported finding relief from the medical symptoms of nausea and vomiting by ingesting or smoking marijuana. Clinical studies show that both smoked marijuana and THC have the ability to reduce vomiting to a certain extent; researchers have discovered cannabinoid receptors in relatively large quantities in the region of the brain that controls visceral sensations such as vomiting and nausea.
Mack, Alison, Joy, Janet. “Front Matter.” Marijuana As Medicine?: The Science Beyond the Controversy. Washington, DC: The National Academies Press, 2000.