Lower esophageal sphincter and gastric acid response to intravenous infusions of synthetic human gastrin I heptadecapeptide.

Human gastrin I heptadecapeptide was administered by constant intravenous infusion to 7 adult male volunteers without gastrointestinal disease, and serum gastrin concentrations and responses of the lower esophageal sphincter (LES) pressure and gastric acid output were measured and compared. Significant responses in LES pressure were found at gastrin infusion rates which produced submaximal gastric acid output. These LES pressure responses were quantitatively smaller than those occurring concomitantly with similar total immunoreactive gastrin levels evoked by administration of a protein meal in the same subjects. These observations suggest that, although increases in serum gastrin concentrations may contribute to increases in LES pressure seen under physiological conditions after feeding, the increase in LES pressure produced by feeding cannot be explained exclusively on the basis of endogenous gastrin release.