“…According to the position of the first double bond present in their structures, this big family can be divided into n-3 (α-linolenic acid (ALA) and its products eicosapentanoic acid (EPA), docosahexaenoic acid (DHA), 20-hydroxyeicosapentaenoic acid (20-HEPE) and 22-hydroxyeicosapentaenoic acid (22-HDoHE)), and n-6 linoleic acid (LA) and its products γ-linoleic acid, arachidonic acid (AA) [ 69 ] (which produces hepoxylin, HXA-3, 14,15-epoxyeicosatrienoic acid, 14,15-EET, and 20-hydroxyeicosatetranoic acid, 20-HETE), 9- and 13-hydroxyoctadecadienoic acids (9-HODE and 13-HODE). Other agonists endogenously secreted are oxytocin [ 70 ], adenosine [ 71 ], nitric oxide [ 72 ], hydrogen sulfide (H 2 S) [ 73 ], lysophosphatidic acid (LPA) [ 74 ] and its derivative diacylglycerol [ 75 ], pH variations [ 76 , 77 ], vitamin D [ 78 ], N-acyl amino acids/neurotransmitters [ 79 ], miRNAs [ 80 , 81 ], prostaglandins, nerve growth factors and the endocannabinoids family, including N-Acyl amides [ 82 ] (N-acyl GABAS [ 83 , 84 ] derived then in D-GABAs, L-GABA and A-GABA) and N-acylethanolamines (NAEs) [ 85 ], such as anandamide (AEA) *** [ 86 ], oleylethanolamine (OEA) [ 87 ] and palmitoylethanolamine (PEA) [ 88 ]. * Product from arachidonic acid.…”