14,15-Leukotriene D4

Others

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14, 15-Leukotriene D4 (14, 15-LTD4) is a member of an alternate class of LTs synthesized by a pathway involving the dual actions of 15- and 12-lipoxygenases (15- and 12-LOs) on arachidonic acid via 15-HpETE and 14, 15-LTA4 intermediates. 14, 15-LTD4 is classified as an eoxin (EXD4), because it is formed mostly by eosinophils. However, mast cells and nasal polyps can synthesize 14, 15-LTD4 as well. Little is known about the physiological actions of 14, 15-LTD4. It has weak contractile activity on both guinea pig ileum and pulmonary parenchyma in contrast to the effects of 5-LO-derived LTs. However, in an in vitro permeability assay, 14, 15-LTD4 can increase vascular permeability of human endothelial cell monolayers, with similar potency to that of 5-LO-derived LTs, resulting in plasma leakage, a hallmark of inflammation.