Tetrahydrocannabinol (THC)
THC, short for tetrahydrocannabinol, is a chemical compound found in cannabis. THC causes cannabis’s intoxicating effects.
In low doses, THC causes some pain reduction, can stimulate appetite, and help reduce nausea. Higher doses may cause the “high” associated with marijuana, leading to altered perception of time and space, feelings of happiness, or feelings of fatigue.
Although THC is not the only source of psychoactive effects in the plant, it is the most abundant chemical that clearly alters subjective experience. THC works by binding with membranes of particular nerve cells in the brain that have special protein receptors called cannabinoid receptors (CB1). Cannabinoids bind with the outer protein of the receptor cell and trigger activity inside. Different cannabinoids bind in different ways, leading to varied amounts of activity within the nerve cell. In comparison to mu opiod receptors, the sites of action for morphine, CB1 receptors are 10 times more abundant in the nervous system. It has been shown that cannabinoids alter the communication between nerve cells, slowing firing rate and decreasing neurotransmitter release. These actions may account for the many effects THC, as well as other cannabinoids has. Clearly identifying the important role cannabinoids can play in the functioning of the brain.
* excerpt taken from Understanding Marijuana a new look at the scientific evidence by Mitch Earleywine
Below are links to research studies and articles on THC: