Intestinal phase of gastric secretion in patients with duodenal ulcer

In 10 healthy subjects and 10 duodenal ulcer patients the intestinal phase of gastric acid secretion was studied by intraduodenal infusion of a 10% liver extract meal (pH 7) at 400 ml/h for three hours. A gastroduodenal double lumen tube with two balloons was used to block the pylorus and to prevent duodenogastric reflux. Gastric acid response to a duodenal meal of liver extract reached a peak at the end of the first hour of infusion of the extract and was then followed by a relatively well-sustained plateau. When the figure was normalised as a percentage of peak response to pentagastrin it was about 45% in healthy subjects and 63% in duodenal ulcer patients. Serum gastrin concentration increased significantly during a duodenal meal of liver extract only in duodenal ulcer patients and not in healthy subjects. The combination of the duodenal meal of liver extract with pentagastrin infusion resulted in a significantly greater increase in acid output in duodenal ulcer patients than in healthy controls. Duodenal perfusion with a liver extract meal in which the pH was gradually decreased caused a pH-dependent reduction in acid output, but not in serum gastrin, both in the duodenal ulcer patients and in healthy subjects. This study shows that the intestinal phase in man results in a potent gastric acid stimulation which is pH-dependent, greatly augmented by pentagastrin, and more vigorous in duodenal ulcer patients than in healthy controls.