Protective effect of fish oil against Indomethacin induced gastric ulcer in rats

Background: Nonsteroidal anti-inflammatory drugs such as indomethacin cause gastrointestinal damage in animals and humans. Objective: To investigate the protective effect of intragastric fish oil on indomethacin induced gastric ulcer in rats. Methods: The adult male rats were divided into 4 groups in which groups I and II were fed normally and groups III and IV were treated with daily 1.6 ml fish oil and sunflower oil for 4 weeks respectively. Gastric ulcer was induced in group II by injection of NaHCO3 and in the other three groups by indomethacin S.C at 20 mg/kg. The lesions in the stomach were measured by a dissecting microscope. The ulcer index, volume, acidity of gastric contents and acid output were also measured. The weight of animals were determined in all groups. Findings: The results indicated that an ulcer index in group III was 54.3% and 58.7% lower than groups I and IV respectively however, no significant difference in ulcer index were seen between groups I and IV. Acid volume and acid concentration in fish oil groups were 70% and 50% lower than group IV. Acid output was also 85.7% and 83.7% lower in groups I and IV respectively. The difference in weight increase between groups I and III were not significant. Conclusion: It is suggested that, fish oil protects the gastric mucosa from indomethacin induced lesions, but sunflower oil dose not have such effect. The inhibitory action of fish oil appears to be mostly related to its antisecretory activity.