title: Leukotriene B4 stimulation of phosphatidylinositol turnover in macrophages and inhibition by pertussis toxin.
abstract: The influence of leukotriene B4 (LTB4) on phosphatidylinositol (PI) cycle activity was investigated in the guinea pig alveolar macrophage. In contrast to the observation reported in leukocytes [(1984) Proc. Natl. Acad. Sci. USA 81, 5966-5969], LTB4 was found to stimulate PI cycle activity in the macrophage (transient decrease in phosphatidylinositol 4,5-bisphosphate and phosphatidylinositol 4-phosphate, transient elevation of 1,2-diacylglycerol and elevation of phosphatidic acid) similar to the stimulation of the PI cycle by the chemotactic formyl peptides. Preincubation of macrophages with 1 microgram/ml of pertussis toxin, for 1 h at 37 degrees C, blocked LTB4 and formyl peptide stimulated O-2 production and PI cycle activity. Therefore, both stimulants are proposed to act through the same coupling protein to activate phospholipase C in the early stages of macrophage activation.
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism; D004075:Diglycerides / Q000378:metabolism; D006168:Guinea Pigs; D007700:Kinetics; D007975:Leukotriene B4 / Q000494:pharmacology*; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism*; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D037342:Pertussis Toxin; D010712:Phosphatidic Acids / Q000378:metabolism; D019269:Phosphatidylinositol 4,5-Diphosphate; D018129:Phosphatidylinositol Phosphates; D010716:Phosphatidylinositols / Q000378:metabolism*; D011650:Pulmonary Alveoli / Q000166:cytology; D013481:Superoxides / Q000378:metabolism; D010566:Virulence Factors, Bordetella / Q000494:pharmacology*
chemical_list: C011439:1,2-diacylglycerol; D004075:Diglycerides; D010712:Phosphatidic Acids; D019269:Phosphatidylinositol 4,5-Diphosphate; D018129:Phosphatidylinositol Phosphates; D010716:Phosphatidylinositols; D010566:Virulence Factors, Bordetella; C037178:phosphatidylinositol 4-phosphate; D013481:Superoxides; D007975:Leukotriene B4; D009240:N-Formylmethionine Leucyl-Phenylalanine; D037342:Pertussis Toxin; D002118:Calcium