title: Gastric healing effect of melatonin against different gastroinvasive agents in cholestatic rats.
abstract: OBJECTIVE
  The frequency of gastrointestinal ulceration is higher in jaundiced patients than in healthy population. The aim of this study was to assess the effect of pretreatment with melatonin, a potent scavenger of reactive oxygen species, on stress-induced gastric ulcers of cholestatic rats.
  
  
  METHODS
  Cholestasis was induced by surgical ligation of bile-duct and sham-operated rats served as sham animals. The animals received saline or melatonin (1, 3 or 10mg/kg) before stress induction. Three different types of gastroinvasive agents including ethanol, indomethacin or water immersion were used as stress agents to induce gastric ulceration.
  
  
  RESULTS
  Gastric mucosal damage induced by different gastroinvasive agents was significantly greater in bile-duct-ligated rats than in sham ones. Melatonin was protective against ethanol-, indomethacin- and water immersion-induced gastric damage in bile-duct-ligated and sham rats, dose-dependently, but the protective effect of melatonin was greater in cholestatic rats than sham rats in all three different series of experiments.
  
  
  CONCLUSIONS
  In conclusion, pretreatment of rats with melatonin protected gastric mucosa of cholestatic rats more effectively than the sham ones possibly by a mechanism involving the scavenging of free radicals.
authors.affiliation: Department of Pharmacology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Leila
authors.initials: L
authors.lastname: Moezi
authors.forename: Somaye
authors.initials: S
authors.lastname: Nasiripoor
authors.forename: Vida
authors.initials: V
authors.lastname: Mohajer
authors.forename: Mona
authors.initials: M
authors.lastname: Maghsoodi
authors.forename: Morteza
authors.initials: M
authors.lastname: Samini
authors.forename: Ahmad R
authors.initials: AR
authors.lastname: Dehpour