leukotriene e-4

Leukotriene E4 (LTE4)（LTE4）通过 二肽酶对LTD4 上的作用生成，是过敏性休克慢反应物质（SRS-A）的成分之一。LTE4 存在于血浆和尿液中，可用于检测哮喘。

Leukotriene E-4 sulfone is a synthetic leukotriene.

Leukotrienes (LTs) are a group of acute inflammatory mediators derived from arachidonic acid in leukocytes. The majority of these metabolites are formed through the 5-lipoxygenase (5-LO) pathway. 14,15-LTE4 is a metabolite of 14,15-LTC4 and 14,15-LTD4, an alternate class of LTs synthesized by a pathway involving the dual actions of 15- and 12-LOs on arachidonic acid via 15-HpETE and 14,15-LTA4 intermediates. These metabolites are classified as eoxins because they are formed mostly by eosinophils. Mast cells and nasal polyps can synthesize 14,15-LTC4 as well, however metabolism to 14,15-LTE4 in these cells and tissue has not been documented. 14,15-LTE4 increases vascular permeability of human endothelial cell monolayers with about 10-fold less potency than LTC4, but approximately 100-fold greater potency than histamine.

Slow isomerization of the C-11 double bond of LTE4 leads to the formation of 11-trans LTE4. 11-trans LTE4 is equipotent to LTE4 in contracting guinea pig ileum.

N-acetyl Leukotriene E4（N-乙酰白三烯 E4）是Leukotriene E4的内源性代谢物，主要通过胆汁排泄，其活性比Leukotriene E4低1~3个数量级，能引起气管的收缩。

Maresin conjugates in tissue regeneration 1 (MCTR1) is a specialized pro-resolving mediator (SPM) synthesized from docosahexaenoic acid in macrophages at the site of inflammation. DHA is oxidized to maresin 1 , which is then converted to MCTR1 by glutathione S-transferase Mu 4 or leukotriene C4 synthase. MCTR1 accelerates tissue regeneration in planaria (1 and 100 nM). Pretreatment with MCTR1 (50 ng mouse, i.p.) prior to E. coli administration reduces neutrophil infiltration, shortens the inflammatory resolution period, and increases phagocytosis of E. coli by macrophages. When administered at a dose of 100 ng 12h post E. coli infection in a mouse model of peritonitis, MCTR1 reduces the amount of eicosanoids in the exudate.

Maresin conjugates in tissue regeneration 2 (MCTR2) is a specialized pro-resolving mediator (SPM) synthesized from docosahexaenoic acid in macrophages at the site of inflammation. DHA is oxidized to maresin 1 , which is converted to MCTR1 by glutathione S-transferase Mu 4 or leukotriene C4 synthase then to MCTR2 by γ-glutamyl transferase. MCTR2 accelerates tissue regeneration in planaria (1 and 100 nM). Pretreatment with MCTR2 prior to E. coli administration reduces neutrophil infiltration, shortens the inflammatory resolution period, and increases phagocytosis of E. coli by macrophages. When administered at a dose of 100 ng 12h post E. coli infection in a mouse model of peritonitis, MCTR2 selectively reduced the amount of the eicosanoids PGD2 and PGF2α in the exudate.

Maresin conjugates in tissue regeneration 3 (MCTR3) is a specialized pro-resolving mediator (SPM) synthesized from docosahexaenoic acid in macrophages. DHA is oxidized to maresin 1 , which is converted to MCTR1 by glutathione S-transferase Mu 4 or leukotriene C4 synthase, then to MCTR2 by γ-glutamyl transferase, and to MCTR3 by dipeptidase. MCTR3 accelerates tissue regeneration in planaria (1 and 100 nM) approximately as potently as MCTR2 and more potently than MCTR1. Pretreatment with MCTR3 prior to E. coli administration in mice reduces neutrophil infiltration, shortens the inflammatory resolution period, and increases phagocytosis of E. coli by macrophages. When administered at a dose of 100 ng 12h post E. coli infection in a mouse model of peritonitis, MCTR3 selectively reduces the amount of the eicosanoids PGD2 , PGE2 , PGF2α , and TXB2 in the exudate.

Ritolukast (Wy-48252) 是一种口服活性的气溶胶白三烯 (LTD4 E4) 受体拮抗剂，可用于抑制气溶胶 LTD4 引起的豚鼠支气管收缩，ID50 为 0.5 mg kg。