Prostaglandin reductase 1 (PTGR1) aka LTB4DH metabolizes eicosanoids by catalysing the oxidation of leukotriene B4 (LTB4) to form 12-oxo-Leukotriene B4 (12-oxoLTB4) aka 12-Keto-LTB4. The gene was originally cloned as leukotriene B4 12-hydroxydehydrogenase (LTB4DH) but was later discovered to have dual functionality as a prostaglandin reductase (Yokomizo et al. 1996). This reaction has been inferred from a reaction in pigs (Yokomizo et al. 1993, Ensor et al. 1998).