Abnormal gastric emptying response to pentagastrin in duodenal ulcer disease

The effect of pentagastrin on gastric emptying in duodenal ulcer disease (DU) is unknown. The evaluation of this effect is complicated by the simultaneous action of the hormone on gastric secretion. We compared gastric emptying and net gastric output in 17 patients with active DU to that of 11 healthy controls. A dye-dilution technique was used to determine net acid output, fractional emptying rate, and acid emptying rate during a basal period and after pentagastrin (6 microgram/kg/hr, intravenously). Net basal acid output observed in controls (54 +/- 10 microEq/min; mean +/- SE) was used as the primary criterion for separating DU patients into 12 normosecretor (30 +/- 10 microEq/min) and 5 hypersecretor patient groups (163 +/- 40 microEq/min). The pentagastrin-stimulated net acid output was significantly greater in hypersecretor patients than in controls (P less than 0.01) but was normal in normosecretor patients. Basal fractional emptying and acid emptying rates were significantly greater in hypersecretors than in controls (P less than 0.05) but were normal in normosecretors. In contrast, both normo- and hypersecretor patients had significantly greater fractional emptying (P less than 0.01) and acid emptying rates than controls (P less than 0.05) during pentagastrin infusion. Thus, a greater load of acid transiently enters the duodenum in duodenal ulcer disease following pentagastrin stimulation, even in the absence of gastric hypersecretion.