Leukotriene B4 (LTB4) is formed from arachidonic acid and is a potent inflammatory mediator. LTB4's activity is terminated by formation of its omega hydroxylated metabolite, 20-hydroxyleukotriene B4 (20OH-LTB4). This deactivation can be carried out by CYP4F3 in addition to CYP4F2 (Kikuta et al. 1998).
monooxygenase activity of Cytochrome P450 (CYP4F3 based) [endoplasmic reticulum membrane]