sentence: Although , this is just an approximate calculation of the extracellular 20-HETE concentration in pancreatic islets , it demonstrates the plausibility of an autocrine mechanism involving 20-HETE and FFAR1 in the regulation of insulin secretion.20-HETE is an eicosanoid metabolite of arachidonic acid , which is produced by ω - hydroxylase members of the cytochrome P450-dependent CYP4 and CYP2 families , in particular CYP4A11 , CYP4A22 , CYP4F2 , CYP4F3 , CYP4V2 , and CYP2U1 in humans and Cyp4a10 , Cyp4a12 , Cyp4f13 , Cyp4f16 , Cyp4v3 , and Cyp2u1 in mice , of which we found several to be expressed in pancreatic islets and β - cells .