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Related to leukotrienes: Thromboxanes

leu·ko·tri·enes (LT),

Products of eicosanoid metabolism (usually, arachidonate) with several physiologic roles, such as mediation of inflammation and participation in allergic reactions; leukotrienes differ from the related prostaglandins and thromboxanes in that they do not have a central ring; so named because they were discovered in association with leukocytes and were initially determined to possess three conjugated double bonds; letters A-F identify the first six metabolites isolated, with subscript numbers to indicate the number of double bonds (for example, leukotriene C4).


a class of biologically active compounds that occur naturally in leukocytes and produce allergic and inflammatory reactions similar to those of histamine. They are thought to play a role in the development of allergic and autoallergic diseases such as asthma, rheumatoid arthritis, inflammatory bowel disease, and psoriasis.


(LT) (lū'kō-trī'ēnz)
Products of eicosanoid metabolism with physiologic roles in inflammation and allergic reactions.
Synonym(s): leucotriene.


Powerful chemical agents released by MAST CELLS, basophil cells and MACROPHAGES and involved in many allergic and other immunological reactions. Leukotrienes are derived from ARACHIDONIC ACID and cause CHEMOTAXIS and increase the leakiness of small blood vessels. In asthma they cause the narrowing of the air passages and the secretion of mucus. They can be inhibited by corticosteroid drugs.


A class of small molecules produced by cells in response to allergen exposure; they contribute to allergy and asthma symptoms.
Cells of the blood.


endogenous chemicals (lipids), derived from arachidonic acid, active in the inflammatory process and some allergic responses, and one of the triggers of asthma. Leukotriene receptor-blocking drugs have been developed as part of the treatment regime for asthma and are particularly useful where exercise-induced symptoms are prominent or when there is associated rhinitis.

leukotrienes (lōō·kō·trī·ēnz),

n.pl regulators of inflammatory and allergic reactions. Biologically active leukotrienes are made up of 20-carbon carboxylic acids derived from arachidonic acid.
References in periodicals archive ?
INV104 (zafirlukast) is a leukotriene receptor antagonist (LTRA) that reduces inflammation, constriction of the airways, and the build-up of mucus in the lungs.
Like zafirlukast, montelukast is a competitive antagonist for the cysteinyl leukotrienes.
Some asthma patients benefit greatly from treatment with anti-leukotriene drugs, which can attenuate the effects of leukotrienes not blocked by steroids.
Prostaglandins, leukotrienes, and other arachidonic acid metabolites in the pathogenesis of otitis media.
Leukotriene receptor antagonists (LTRAs) are suitable options that are given orally
Mucous becomes too abundant, the fluid adds up to swelling, and histamines and leukotrienes irritate nerve endings into the familiar symptoms of burning and itching and sneezing.
It works by blocking the main cause of inflammation - a chemical called leukotriene.
Researchers know that certain immune cells, including a class known as mast cells, produce leukotrienes by using the enzyme 5-lipoxygenase to break down arachidonic acid, a fatty acid.
Leukotrienes are inflammatory mediators in asthma that can trigger asthma symptoms, including inflammation, swelling, bronchoconstriction and mucus secretion.
Leukotrienes are implicated in numerous inflammatory processes.
GLA is further metabolized to dihomogamma linlenic acid (DGLA) which undergoes oxidative metabolism by cyclooxygenases and lipoxygenases to produce anti-inflammatory eicosanoids (prostaglandins of series 1 and leukotrienes of series 3).
Richard P Bazinet takes over the editorship of PLEFA (Prostaglandins, Leukotrienes and Essential Fatty Acids), from Mehar Manku, who remains as Editor Emeritus.