Tetrahydrocannabinol (THC)

Tetrahydrocannabinol is the principal psychoactive constituent (or cannabinoid) of the cannabis plant. The presence of these specialized cannabinoid receptors in the brain led researchers to the discovery of endocannabinoids, such as anandamide and 2-arachidonoyl glyceride (2-AG). THC targets receptors in a manner far less selective than endocannabinoid molecules released during retrograde signaling, as the drug has a relatively low cannabinoid receptor efficacy and affinity. In populations of low cannabinoid receptor density, THC may act to antagonize endogenous agonists that possess greater receptor efficacy. THC is a lipophilic molecule and may bind non-specifically to a variety of receptors in the brain and body, such as adipose tissue (fat). THC is metabolized mainly to 11-OH-THC by the body.