title: Inhibition of bovine lymphocyte response to phytohemagglutinin by a specific 5-lipoxygenase inhibitor.
abstract: AA861, a specific 5-lipoxygenase inhibitor, inhibited bovine lymphocyte response to phytohemagglutinin (PHA). Mitogen-stimulated cultures of mononuclear cells produced leukotriene B4 (LTB4) in 24 hours. The production of LTB4 was completely inhibited by concentrations of AA861 that inhibited mitogen-induced 3H-thymidine incorporation. The inhibition of lymphocyte proliferation was totally reversed by LTB4 but not by leukotriene C4 or leukotriene D4. The inhibition of interleukin-2 (IL-2) production by AA861 was also completely reversed by addition of exogenous LTB4 to lymphocyte cultures. Thus, endogenous LTB4 production appeared to be necessary for PHA-induced IL-2 production and lymphocyte proliferation.
mesh_terms: D000818:Animals; D001091:Arachidonate Lipoxygenases / Q000037:antagonists & inhibitors*; D016227:Benzoquinones; D002417:Cattle; D002478:Cells, Cultured; D066298:In Vitro Techniques; D007376:Interleukin-2 / Q000096:biosynthesis; D007975:Leukotriene B4 / Q000096:biosynthesis*; D016859:Lipoxygenase Inhibitors; D008213:Lymphocyte Activation / Q000187:drug effects*; D008214:Lymphocytes / Q000187:drug effects / Q000502:physiology*; D010835:Phytohemagglutinins / Q000494:pharmacology; D011809:Quinones / Q000494:pharmacology*; D013189:SRS-A / Q000096:biosynthesis
chemical_list: D016227:Benzoquinones; D007376:Interleukin-2; D016859:Lipoxygenase Inhibitors; D010835:Phytohemagglutinins; D011809:Quinones; D013189:SRS-A; D007975:Leukotriene B4; C036837:2,3,5-trimethyl-6-(12-hydroxy-5,10-dodecadiynyl)-1,4-benzoquinone; D001091:Arachidonate Lipoxygenases