The first cannabinoid receptor, CB1, was identified and characterised in 1988 and cloned in 1990. A second, CB2, was cloned in 1993 by a group in Cambridge looking for a receptor that could explain more of the effects of THC; it gave a molecular explanation for the action of cannabinoids on the immune system. Together with the body's own cannabinoids they make up the endocannabinoid system.[1][2]
References
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