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The endocannabinoid system (ECS) is a group of endogenous cannabinoid receptors located in the mammalian brain and throughout the central and peripheral nervous systems, consisting of neuromodulatory lipids and their receptors. Known as "the body’s own cannabinoid system",〔 the ECS is involved in a variety of physiological processes including appetite, pain-sensation, mood, and memory, and in mediating the psychoactive effects of cannabis. Two primary endocannabinoid receptors have been identified: CB1, first cloned in 1990; CB2, cloned in 1993. CB1 receptors are found predominantly in the brain and nervous system, as well as in peripheral organs and tissues, and are the main molecular target of the endocannabinoid ligand (binding molecule), Anandamide, as well as its mimetic phytocannabinoid, THC. One other main endocannabinoid is 2-Arachidonoylglycerol (2-AG) which is active at both cannabinoid receptors, along with its own mimetic phytocannabinoid, CBD. 2-AG and CBD are involved in the regulation of appetite, immune system functions and pain management. ==Basic overview== The endocannabinoid system, broadly speaking, includes: * The endogenous arachidonate-based lipids, anandamide (''N''-arachidonoylethanolamide, AEA) and 2-arachidonoylglycerol (2-AG); these are known as "endocannabinoids" and are physiological ligands for the cannabinoid receptors. Endocannabinoids are all eicosanoids. * The enzymes that synthesize and degrade the endocannabinoids, such as fatty acid amide hydrolase or monoacylglycerol lipase. * The cannabinoid receptors CB1 and CB2, two G protein-coupled receptors that are located in the central and peripheral nervous systems. The neurons, neural pathways, and other cells where these molecules, enzymes, and one or both cannabinoid receptor types are all colocalized form the endocannabinoid system. The endocannabinoid system has been studied using genetic and pharmacological methods. These studies have revealed that cannabinoids act as neuromodulators for a variety of processes, including motor learning, appetite,〔 and pain sensation, among other cognitive and physical processes. The localization of the CB1 receptor in the endocannabinoid system has a very large degree of overlap with the orexinergic projection system, which mediates many of the same functions, both physical and cognitive.〔 Moreover, CB1 is colocalized on orexin projection neurons in the lateral hypothalamus and many output structures of the orexin system,〔 where the CB1 and orexin receptor 1 (OX1) receptors physically and functionally join together to form the CB1–OX1 receptor heterodimer.〔 (Figure 1: Schematic of brain CB1 expression and orexinergic neurons expressing OX1 or OX2 ) (Figure 2: Synaptic signaling mechanisms in cannabinoid and orexin systems ) (Figure 3: Schematic of brain pathways involved in food intake )〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Endocannabinoid system」の詳細全文を読む スポンサード リンク
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