Animal models of gastroduodenal ulcer disease.

Animal models have played a significant role in research that aims to understand peptic ulceration. Firstly, they have helped define basic mechanisms of gastric mucosal defence and repair. The basis for gastric injury following NSAID administration was facilitated by animal models that correlated well with disease in humans. In early studies, ulceration was induced by grossly damaging insults to the gastric mucosa that were unphysiological. With refinement these models provided a clearer appreciation of stress ulceration. The discovery of Helicobacter pylori (H. pylori), as the cause of most ulcers, resulted in a need to re-evaluate the early literature and to look for new models. To date, these have contributed little to our understanding of the pathogenesis of H. pylori-induced ulcer. A major aim of this chapter is to suggest that thorough understanding of the animal models of Helicobacter infection may provide important new insights, in particular the factors controlling gastritis, the essential precursor lesion of ulceration. Available models include primates, cats, guinea pigs, ferrets and pigs. The mouse models provide opportunity for identifying both essential bacterial and host factors. The most severe pathologies are seen in the H. pylori-infected Mongolian gerbil with ulcers being formed in most animals. This is likely to become the standard animal model for investigation of peptic ulcer disease.