ABSTRACT
Leukotrienes are lipid mediators with profound biologic effects. Leukotriene B4 (LTB4), a dihydroxy leukotriene, is a potent modulator of polymorphonuclear leukocytes (PMN). It induces chemotaxis, chemokinesis, aggregation, and degranulation of PMN (1-3) and causes PMN to adhere to endothelial cells (4). LTB4 can act synergistically with vasodilators to promote vascular leakage (5). These effects implicate LTB4 as mediators of certain inflammatory diseases. The cysteinyl leukotrienes, LTC4, LTD4, and LTE4, are cystine-containing leukotrienes that are historically known as slow-reacting substances of anaphylaxis (SRS-A) (6). The cysteinyl leukotrienes are the most potent contractile agonists for human bronchial smooth muscle (7) and thus are implicated in the pathogenesis of asthma.
