title: Effect of Neutrophils on Nitric Oxide Production from Stimulated Macrophages.
abstract: BACKGROUND
  During the initial phase of an infection, there is an upregulation of inducible nitric oxide synthase in the macrophages for the production of nitric oxide. This is followed by the recruitment of polymorphonuclear leukocytes (neutrophils) which release arginase. Arginase competes with inducible nitric oxide synthase for a common substrate L-arginine.
  
  
  OBJECTIVE
  To investigate whether the entry of neutrophils and release of arginase can interfere with nitric oxide production from stimulated mouse macrophages.
  
  
  METHODS
  Neutrophils were isolated from human blood and stimulated with cytodex-3 beads. Cultured macrophages were stimulated with lipopolysaccharide and interferon gamma with or without N (G)-nitro-L-arginine methyl ester or N (omega)-hydroxy-nor-L-arginine. Measurement of NO2-/NO3- and urea were done using the spectrophotometer.
  
  
  RESULTS
  A significantly higher level of nitric oxide production from stimulated macrophages was observed compared to control. There was a decrease in nitric oxide production when stimulated macrophages were treated with the supernatant from activated neutrophils (p<0.05).
  
  
  CONCLUSIONS
  Arginase from neutrophils can modulate nitric oxide production from activated macrophages which may affect the course of infection by intracellular bacteria.
authors.affiliation: Department of Clinical and Experimental Medicine, Division of Medical Microbiology, Linkoping University, Linköping, Sweden, e-mail: eriad828@student.liu.se.
authors.forename: Eric
authors.initials: E
authors.lastname: Adua
authors.forename: Frank Oteng
authors.initials: FO
authors.lastname: Danso
authors.forename: Oswald Mensah
authors.initials: OM
authors.lastname: Boa-Amponsem
authors.forename: Frank
authors.initials: F
authors.lastname: Adusei-Mensah
mesh_terms: D000818:Animals; D001119:Arginase / Q000096:biosynthesis / Q000378:metabolism*; D001120:Arginine / Q000031:analogs & derivatives / Q000494:pharmacology; D002460:Cell Line; D003911:Dextrans / Q000276:immunology; D006801:Humans; D007371:Interferon-gamma; D008070:Lipopolysaccharides; D008262:Macrophage Activation / Q000276:immunology; D008264:Macrophages / Q000276:immunology*; D051379:Mice; D009169:Mycobacterium tuberculosis / Q000276:immunology; D009504:Neutrophils / Q000276:immunology*; D009569:Nitric Oxide / Q000096:biosynthesis*; D052247:Nitric Oxide Synthase Type II / Q000037:antagonists & inhibitors / Q000378:metabolism*; D019335:Nitroarginine / Q000494:pharmacology
chemical_list: D003911:Dextrans; D008070:Lipopolysaccharides; D019335:Nitroarginine; C026512:arginine methyl ester; D009569:Nitric Oxide; C052839:Cytodex; D007371:Interferon-gamma; D001120:Arginine; C496319:NOS2 protein, human; D052247:Nitric Oxide Synthase Type II; D001119:Arginase