Aspirin and gastric ulceration: light and electron microscopic observations in a model of aspirin plus stress-induced ulcerogenesis.

The gastric mucosa of rats given aspirin orally and concomitantly exposed to mild (cold) stress conditions has been examined under the electron microscope. In this model of gastric ulceration greater involvement is seen of the parietal and zymogen cells than is evident after aspirin treatment alone (which leads to mucosal erosions but not ulceration per se). Evidence of considerable autolytic and proteolytic activity is seen in aspirin-plus-stress-treated animals developing in ulceration. Little damage was observed in animals exposed to these mild stress conditions. The synergistic interaction between aspirin and stress could have its basis in greater sensitizing of parietal and zymogen cells to damage not seen in aspirin-treated animals.