[The role of free radicals in inflammatory states, ulceration, and ulcers of the stomach and duodenum].

The free radicals derived from oxygen have been implicated in damage caused to the gastroduodenal mucosa. The association between the mucosal production of reactive oxygen radicals in the gastric antrum and duodenum, Helicobacter pylori density and duodenal ulcer has been previously described. The role of interleukin IL-8 in the inflammatory process and its relationship with reactive oxygen radicals has also been investigated. These results indicate that oxygen radicals play an important role in the mechanism of ulcer aggravation induced by a variety of different factors.