title: Nitric oxide-induced inhibition of mouse paw edema: involvement of soluble guanylate cyclase and potassium channels.
abstract: OBJECTIVE
  To investigate the effect of nitric oxide (NO) donors on inflammatory mouse paw edema (MPE).
  
  
  METHODS
  Mice previously treated with sodium nitroprusside (SNP; 1.5, 5 and 10 micromol/kg) or S-nitroso-N-acetyl-DL-penicillamine (SNAP; 7, 14 and 28 micromol/kg) were injected with inflammatory mediators in the paw. Paw edema, myeloperoxidase activity and vascular dye leakage were measured.
  
  
  RESULTS
  Pre-treatment with SNP and SNAP (4 h or 12 h) reduced (approximately 50%) MPE induced by carrageenan, dextran sulfate, bradykinin and histamine but not by serotonin. Pre-treatment with SNP also inhibited carrageenan-induced increases in myeloperoxidase activity and vascular dye leakage. Methylene blue blocked the SNP-induced reduction in MPE when injected 30 min before or 2 h after SNP, but not 4 or 6 h after the NO donor. Tetraethylammonium blocked the SNP-induced reduction in MPE if injected 30 min before or 2, 4 or 6 h after SNP.
  
  
  CONCLUSIONS
  NO donors have a long-lasting anti-inflammatory effect in MPE, which involves guanylate cyclase and tetraethylammonium-sensitive potassium channels.
authors.affiliation: Departamento de Farmacologia, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil,
authors.forename: D
authors.initials: D
authors.lastname: Fernandes
authors.forename: J E
authors.initials: JE
authors.lastname: Da Silva-Santos
authors.forename: J
authors.initials: J
authors.lastname: Assreuy
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D001920:Bradykinin / Q000494:pharmacology; D002351:Carrageenan / Q000008:administration & dosage / Q000494:pharmacology; D016264:Dextran Sulfate / Q000494:pharmacology; D004487:Edema / Q000139:chemically induced / Q000188:drug therapy* / Q000378:metabolism / Q000517:prevention & control; D005260:Female; D006162:Guanylate Cyclase / Q000378:metabolism*; D006632:Histamine / Q000494:pharmacology; D007279:Injections, Subcutaneous; D051379:Mice; D009569:Nitric Oxide / Q000378:metabolism*; D020030:Nitric Oxide Donors / Q000008:administration & dosage / Q000494:pharmacology*; D009599:Nitroprusside / Q000008:administration & dosage / Q000494:pharmacology; D010396:Penicillamine / Q000031:analogs & derivatives* / Q000494:pharmacology; D009195:Peroxidase / Q000378:metabolism; D015221:Potassium Channels / Q000378:metabolism*; D051381:Rats; D012701:Serotonin / Q000494:pharmacology; D013997:Time Factors
chemical_list: D020030:Nitric Oxide Donors; D015221:Potassium Channels; C110881:S-nitro-N-acetylpenicillamine; D009599:Nitroprusside; D009569:Nitric Oxide; D012701:Serotonin; D006632:Histamine; D002351:Carrageenan; D016264:Dextran Sulfate; D009195:Peroxidase; D006162:Guanylate Cyclase; D010396:Penicillamine; D001920:Bradykinin