Relationship of plasma motilin response to lower esophageal sphincter pressure in man.

The effect of intraduodenal instillation of 0.1 N hydrochloric acid or 0.9% saline (control) on lower esophageal sphincter pressure (LESP) and plasma motilin concentrations was studied in five normal volunteers. After acid, LESP and plasma motilin rose concomitantly exceeding basal by about 80% (p less than 0.025) and 90% (p less than 0.05), respectively, at 3 to 4 minutes. Control values did not significantly differ throughout the test period from the mean basal level. These results are compatible with the view that the increase in LESP after duodenal acidification may be mediated by endogenously released motilin.