Receptor and Nonreceptor Membrane-Mediated Effects of THC and Cannabinoids

Abstract

A strict chemical nomenclature is first proposed. It is based on the definitions of cannabinoids, psychoactive (THC) and nonpsychoactive (CBD, CBN, and THC-11 oic acid), and of identified receptors (AEA and G protein) and their physiological ligands (arachidonyl ethanolamine [AEA] and arachidonyl diglycerol [2-AG]). THC is the only natural cannabinoid that interacts with a receptor protein in a stereospecific fashion, a property which is associated with its psychoactivity. Other natural, nonpsychoactive cannabinoids, CBN and CBD, vary over a wide range of concentration in marihuana preparations and antagonize the effects of THC. They also possess biological properties, activating membrane enzymes (phosphorylase and acyltransferase) that increase arachidonic acid biosynthesis.