Cannabis central nervous system cannabinoid receptors

Cannabis sativa plants contain at least 400 different compounds, of which as many as 60 are structurally related to 5 -tetrahydrocannabinol (5 -THC), the primary psychoactive constituent of cannabis. When cannabis is smoked, hundreds of additional compounds are produced by pyrolysis, which may contribute to both acute and chronic effects (Abood and Martin, 1992). The central nervous system actions of canna-binoids are mediated primarily through the CBj receptor. A second type of cannabinoid receptor, termed the CB2 receptor, is distributed primarily in the periphery (Gifford et ah, 1999). Activation of central cannabinoid receptors modulates neurotransmitter release at... 

Dean B, Sundram S, Bradbury R, Scarr E, Copolov D. 2001. Studies on [3H] CP-55940 binding in the human central nervous system Regional specific changes in density of cannabinoid-1 receptors associated with schizophrenia and cannabis use. Neuroscience 103 9-15. 

The primary active component of cannabis is A9-tetrahy-drocannabinol (THC), which is responsible for the greater part of the pharmacological effects of the cannabis complex. A8-THC is also active. However, the cannabis plant contains more than 400 chemicals, of which some 60 are chemically related to A9-THC, and it is evident that the exact proportions in which these are present can vary considerably, depending on the way in which the material has been harvested and prepared. In man, A9-THC is rapidly converted to 11-hydroxy-A9-THC (5), a metabolite that is active in the central nervous system. A specific receptor for the cannabinols has been identified it is a member of the G-protein-linked family of receptors (6). The cannabinoid receptor is linked to the inhibitory G-protein, which is linked to adenyl cyclase in an inhibitory fashion (7). The cannabinoid receptor is found in highest concentrations in the basal ganglia, the hippocampus, and the cerebellum, with lower concentrations in the cerebral cortex. 

Advances in the understanding of endogenous control of pain were obtained with cannabinoids. Throughout history, Cannabis sativa L. has been used as a natural therapeutic herb as well as an analgesic. The Cannabis plant contains a complex mixture of substances that include at least 60 different cannabinoids, including A9-tetrahydrocannabinol (THC) [29]. Pharmacological studies have demonstrated that THC and other active cannabinoids act at specific receptors called CB1 and CB2 [30]. The cannabinoid receptors are expressed in both the peripheral and central nervous system and are endogenously activated by... 

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