Leukotriene

Leukotrienes ( from Ancient Greek λευκός leukos "white" and an ancient Greek τρεῖς, τρία treis, tria "three" ) were detected in leukocytes ( white blood cells) and are chemically derived from arachidonic acid, a polyunsaturated fatty acid four. You have three conjugated double bonds and belong to the group of eicosanoids. Your role in metabolism is related to allergic or inflammatory reactions of the body (eg, asthma ).

The enzyme arachidonate 5-lipoxygenase catalyzes the reaction from arachidonic acid to 5- hydroperoxyeicosatetraenoic acid (5- HPETE ) to leukotriene A4 ( LTA4 ). The very unstable epoxide LTA4 is the direct parent compound for the biosynthesis of various leukotrienes. The substance group is divided into the peptidoglycan ( cysteinyl ) leukotrienes LTC4, LTD4 and LTE4 and the cysteinyl free LTB4, which are obtained using the enzymes LTA4 hydrolase, LTC4 synthase, γ - glutamyl transferase, and the dipeptidase 2. The last two reactions starting from LTC4, assume the export of LTC4 from the cell using the Multidrug Resistance -Related protein 1 ( MRP1 ).

In the synthesis of leukotrienes, 5- lipoxygenase activating protein (FLAP ), a regulating or inducing ( triggering ) plays role.

Montelukast, pranlukast and zafirlukast are leukotriene receptor antagonists. Zileuton is a leukotriene synthesis inhibitor. Such Leukotrienhemmer are effective against bronchial asthma.