Effect of atropine and metoclopramide on serum gastrin response to protein in patients with duodenal ulcers.

The serum gastrin response to Oxo or to a meal was studied in 35 patients with duodenal ulcers and in 28 control subjects. Neither the integrated gastrin response nor the mean peak gastrin concentration was significantly higher in patients with duodenal ulcers compared with the controls, whatever stimulus was used (Oxo or a meal). Atropine 0,5 mg injected intramuscularly half an hour before the meal did not significantly affect the integrated gastrin response or the peak gastrin concentration of controls or of patients with duodenal ulcers. Metoclopramide 10 mg injected intramuscularly half an hour before the meal significantly reduced the integrated gastrin response and, to a lesser degree, the peak gastrin concentration in controls, but it did not affect these variables in patients with duodenal ulcers. The failure to suppress the gastrin response with metoclopramide in patients with duodenal ulcers has not been explained.