Pentapeptide infusion test.

Pentapeptide infused intravenously in graded doses provoked at a dose of 1.5 microg per kg per hour a peak HCl output, which was significantly higher than the HCl secretion induced by intravenous histamine in a dose of 40 microg per kg per hour in five healthy subjects. Pentapeptide infusion test at a dose of 1.5 microg per kg per hour appears to be a very reproducible and safe mode of gastric stimulation, giving a sustained and high level of gastric secretion in 20 subjects, including 10 healthy men and 10 duodenal ulcer patients. Infusion test with pentapeptide has some advantage over histamine stimulation in so far as it is safe, and almost completely free of side-effects. No difference in the response curves to pentapeptide and histamine was found between the normal subjects and duodenal ulcer patients.