Oleamide, amide primaria dell’acido oleico, come ligando essenziale per i recettori dei cannabinoidi nell’uomo

As in the case of endogenous morphin and opiate system, in mammals, much surprise aroused the discovery, in the course of the past decade, of the existence in central and peripheral nervous system (CNS, and PNS of an endogenous cannabinoid system ("endocannabinoids"), ECS) which are ligands of the same cell membrane receptors (CBs) for xenobiotic cannabinoids, particularly for the major of them, the Δ 9 tetrahydrocannabinol, (THC). Thus, endocannabinoids chemically are primary amides and esters of fatty acids which generally bind to CBs (CB1 and CB2), mimicking the pharmacological effects of exogenous cannabinoids. Ecceptionally, however, oleamide, the primary amide of oleic acid, seems do not show any affinity for binding to CBs, even though it exerts some of the cannabinoid-induced actions such as, for instance, analgesic effects and physiological sleeping in animals experimentally sleepless. It has been observed that oleamide induces such effects by selectively binding to serotonergic 5-HT2A/2C 5-HT7e 5-HT1A receptors, and inactivating intercellular communications by blocking in a structurally specific manner ion channels at the gap junctions of glial cells in vitro. Cannabinoid receptors and their endogenous ligands constitute a novel modulatory system presumably involved in specific brain functions, such as nociception, control of movement, memory and neuroendocrine regulations. Some of the clearcut evidences were discussed indicating that endocannabinoids also function in mammals during embryofetal development. Authors highlightening this finding rise the question whether this system may be involved in the modulation and control of brain development in the course of embryofetal life and the first periods of postnatal development.