title: Effects of melatonin or acetylsalicylic acid on gastric oxidative stress after bile duct ligation in rats.
abstract: BACKGROUND
  Antioxidant enzyme activities decrease after bile duct ligation. The aim of this study was to assess the effect of melatonin and acetylsalicylic acid on antioxidant enzyme activities in gastric oxidative stress induced by bile duct ligation.
  
  
  METHODS
  Sixty-four animals were divided into eight groups of eight rats each. Male Sprague-Dawley rats were subjected to either a sham operation or common bile duct ligation (BDL) before treatment with melatonin (MEL) or acetylsalicylic acid (ASA). Gastric superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) activities, and malondialdehyde (MDA) and nitric oxide (NO) levels were determined by spectrophotometers and evaluated.
  
  
  RESULTS
  Our results indicated that BDL caused a significant increase in lipid peroxidation, whereas coadministration of MEL with ASA significantly decreased MDA and NO levels in BDL rats. Moreover, coadministration of MEL and ASA increased antioxidant enzyme activities after the BDL, and these increases were statistically significant for CAT and GPx. On the other hand, the increase in SOD activity was not significant.
  
  
  CONCLUSIONS
  Melatonin administration, either alone or together with acetylsalicylic acid, decreases lipid peroxidation and increases antioxidant enzyme activities in gastric tissues of rats after bile duct ligation. ASA administration, however, either alone or with a vehicle, increases lipid peroxidation and decreases antioxidant enzyme activities.
authors.affiliation: Department of Physiology, Medical School, Inonu University, Malatya, Turkey.
authors.forename: Alaaddin
authors.initials: A
authors.lastname: Polat
authors.forename: Memet Hanifi
authors.initials: MH
authors.lastname: Emre
mesh_terms: D000818:Animals; D001241:Aspirin / Q000494:pharmacology*; D001652:Bile Ducts / Q000502:physiology*; D002374:Catalase / Q000378:metabolism; D002779:Cholestasis / Q000378:metabolism*; D004195:Disease Models, Animal; D005979:Glutathione Peroxidase / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D008550:Melatonin / Q000494:pharmacology*; D018384:Oxidative Stress / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D008315:Malondialdehyde; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D008550:Melatonin; D001241:Aspirin