Current usage limits the term to the leukotrienes (LT) and three types of prostanoids—prostaglandins (PG) prostacyclins (PGI), and thromboxanes (TX).
However, several other classes can technically be termed eicosanoid, including the eoxins, hepoxilins, resolvins, isofurans, isoprostanes, lipoxins, epi-lipoxins, epoxyeicosatrienoic acids (EETs) and endocannabinoids.
[5][6][7][8] The classic eicosanoids are autocrine and paracrine mediators, active at micromolar concentrations (or lower), produced with high stereospecificity.
They are produced from EFAs (chiefly AA) from either cyclooxygenase (COX) or 5-lipoxygenase.
Broadly, the nonclassic eicosanoids are the products of 20-carbon EFAs and [9] Also included are