|MadSci Network: Neuroscience|
Marijuana contains several chemicals called cannabinoids. The best characterized is delta9-tetrahydrocannabinol (delta9-THC), which has psychoactive properties (it's what makes you feel "stoned"). Delta9-THC has been shown to increase food consumption in humans and laboratory animals (see for example REFERENCE 1 and the references therein). This effect is probably dependent on the actions of delta9-THC in a part of the brain termed the hypothalamus, which is involved in controlling feeding behavior; however, other brain regions also may be involved. Cannabinoids work in the body by binding to what are called cannbinoid (CB) "receptors". There are endogenous compounds, one of which is called anandamide, in your body which bind to these receptors. The ability of delta9-THC to produce the "munchies" is likely to mediated by the so-called CB1 receptor. This concludion is based on the demonstration that anandamide induces increased food consumption by acting on CB1 receptors (REFERENCE 2) One of the most promising clinical uses of the cannabinoids is as an appetite stimulant for AIDS and cancer patients (see REFERENCE 3, which is a well written review article on the medical uses of marijuana). REFERENCES 1 Williams et al. (1998) Physiol. Biol. Behav. 65, 343-346 2 Williams and Kirkham (1999) Psychopharmacology 143, 315-317. 3) Rosentahl and Kleber (1999) Proceedings of the Association of American Physicians 111, 159-165.
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