<prompt> All of the following are true regarding about Arachidonic acid AA pathway, except:Aspirin inhibits arachidonic acid pathwayCytosolic Ca2 leads to activation of membrane phospholipase A2Action of phospholipase A2 causes synthesis of arachidonic acidLeukotrienes C4, D4 cause vasodilation  <response>: Cellular phospholipases, mainly phospholipase A2, release arachidonic acid AA from membrane phospholipids. Activation of phospholipase A2 is triggered by increase in cytosolic Ca2 and activation of various kinases in response to external stimuli. Cyclo-oxygenase inhibitors such as aspirin, indomethacin inhibit activity of cyclo-oxygenase involved in conversion of AA into prostaglandins. Leukotriene A4, B4 cause chemotaxis. Leukotrienes C4 and D4 cause vasoconstriction and increase vascular permeability. Leukotrienes C4, D4, E4 are SLOW REACTING SUBSTANCE OF ANAPHYLAXIS SRS-A. Action Examples Vasodilation PGI2, PGE1, PGE2, PGD2 Vasoconstriction Thromboxane A2, leukotriene C4, D4, E4 Increase vascular permeability Leukotriene C4, D4, E4 Chemotaxis, leukocyte adhesion Leukotriene B4 Smooth muscle contraction PGC4, PGD4, PGE4 