The occurrence of duodenal and gastric ulceration in dogs when a segment of duodenum containing the bile and pancreatic ducts was transplanted to the terminal ileum was reported in 1953. The interposition of the duodenal segment in the midportion of the small intestine was not associated with the development of ulceration.1,2 Later studies indicated that acid secretion, as measured by Heidenhain pouches, was similar in the 2 preparations.5
Dragstedt and his associates4 who studied the mechanism of the development of the Exalto-Mann-Williamson ulcer suggested that the failure of the development of ulcerations in the preparation in which the duodenal segment was interposed in the jejunum was due to the protective action of regurgitated duodenal juices. Our study was undertaken to test this hypothesis.
Adult mongrel dogs were used. The initial stage of the experiment was the isolation of a segment of the duodenum which contained the