Leukotriene E4 (LTE4)

Leukotrienes are naturally produced eicosanoid lipid mediators. Leukotrienes use both autocrine signalling and paracrine signalling to regulate the body's response. Leukotrienes are produced in the body from arachidonic acid by the enzyme 5-lipoxygenase. Their production usually accompanies the production of histamine.There has also been postulated the existence of LTG4, a metabolite of LTE4 in which the cysteinyl moiety has been oxidized to an alpha-keto-acid . 

Leukotriene E4 is a leukotriene.Leukotriene E4 (LTE4) and histamine excreted into the urine reflect the in vivo synthesis and release of cysteinyl leukotrienes and histamine, respectively.leukotriene E4 levels in arterialblood reflect the severity of COPD lung and oral prednisolone reduces the plasma levels of leukotriene E4 in patients with COPD.