TY - CHAP M1 - Book, Section TI - Lipid-Derived Autacoids: Eicosanoids and Platelet-Activating Factor A1 - Hilal-Dandan, Randa A1 - Brunton, Laurence L. PY - 2016 T2 - Goodman and Gilman's Manual of Pharmacology and Therapeutics, 2e AB - Membrane lipids supply the substrate for the synthesis of eicosanoids and platelet-activating factor (PAF). Eicosanoids—arachidonate metabolites, including prostaglandins (PGs), prostacyclin (PGI2), thromboxane A2 (TxA2), leukotrienes (LTs), lipoxins, and hepoxilins—are not stored but are produced by most cells when a variety of physical, chemical, and hormonal stimuli activate acyl hydrolases that make arachidonate available. Membrane glycerophosphocholine derivatives can be modified enzymatically to produce PAF. PAF is formed by a smaller number of cell types, principally leukocytes, platelets, and endothelial cells. Eicosanoids and PAF lipids contribute to inflammation, smooth muscle tone, hemostasis, thrombosis, parturition, and gastrointestinal secretion. Several classes of drugs, most notably aspirin, the traditional nonsteroidal anti-inflammatory agents (tNSAIDs), and the specific inhibitors of cyclooxygenase-2 (COX-2), such as the coxibs, owe their principal therapeutic effects to blockade of eicosanoid formation. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/03/28 UR - accesspharmacy.mhmedical.com/content.aspx?aid=1127551160 ER -