Gastric healing effect of melatonin against different gastroinvasive agents in cholestatic rats

• Published in: Pathophysiology (Amsterdam) 2010-02, Vol.17 (1), p.65-70
• Main Authors: Moezi, Leila, Nasiripoor, Somaye, Mohajer, Vida, Maghsoodi, Mona, Samini, Morteza, Dehpour, Ahmad R.
• Format: Article
• Language: English
• Subjects: Cholestasis; Gastroinvasive agents; Melatonin; Rat; Ulcer
• ISSN: 0928-4680; 1873-149X
• DOI: 10.1016/j.pathophys.2009.08.001

Background and 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. Materials and 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 10 mg/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.