title: Enhanced generation of leukotriene B4 from calcium ionophore-stimulated rat peritoneal inflammatory cells: a possible clinical relevance.
abstract: Leukotrienes (LTs) producing capacity was investigated in calcium ionophore A23187-stimulated peripheral white blood cells and peritoneal inflammatory cells suspension isolated from the same rat. A reverse phase high performance liquid chromatography technique and computerized UV spectroscopy were employed to isolate and quantitate the released LTs namely, LTC(4) and LTB(4). Preincubation of rat peritoneal inflammatory cells at 37 degrees C for 5 min followed by calcium ionophore A23187 stimulation for another 5 min produced significantly elevated amounts of LTB(4) as compared to peripheral white blood cells isolated from the same rat (103+/-12.7 versus 40+/-3.6 pmol/10(7) cells, respectively; mean+/-SEM). Enhanced generation of LTB(4) was associated with production of similar amounts of LTC(4) as compared with LTC(4) produced by peripheral white blood cells (15.2+/-4.2 versus 14.6+/-2 pmol/10(7) cells, respectively). In subsequent experiments, when peritoneal inflammatory cells and white blood cells suspension isolated from the same rats were stimulated with calcium ionophore A23187 (1 micro M) after preincubation with different concentrations of exogenous arachidonic acid (1, 3 and 10 micro M), significantly higher amounts of LTB(4) were produced by the peritoneal inflamed cells while a similar amounts of LTC(4)were produced by both types of cells. Increased LTB(4) formation by rat peritoneal inflammatory cells may prove to be of pathophysiological relevance, since this compound has been described to play an important role in acute inflammatory reaction.
authors.affiliation: Department of Pharmacology, Faculty of Pharmacy, King Saud University, P. O. Box 2457, Riyadh 11451, Saudi Arabia. mansour1960us@yahoo.com
authors.forename: Mahmoud A
authors.initials: MA
authors.lastname: Mansour
authors.forename: Othman A
authors.initials: OA
authors.lastname: Al-Shabanah
mesh_terms: D000818:Animals; D016718:Arachidonic Acid / Q000494:pharmacology; D000001:Calcimycin / Q000494:pharmacology*; D002351:Carrageenan; D002851:Chromatography, High Pressure Liquid; D066298:In Vitro Techniques; D007476:Ionophores / Q000494:pharmacology*; D007958:Leukocyte Count; D007962:Leukocytes / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D007975:Leukotriene B4 / Q000096:biosynthesis*; D008297:Male; D010529:Peritoneal Cavity / Q000166:cytology; D010538:Peritonitis / Q000139:chemically induced / Q000378:metabolism* / Q000473:pathology; D051381:Rats; D013056:Spectrophotometry, Ultraviolet
chemical_list: D007476:Ionophores; D007975:Leukotriene B4; D016718:Arachidonic Acid; D000001:Calcimycin; D002351:Carrageenan