Evidence of a non-vagal mechanism of pancreatic polypeptide release in man

Abstract

The Pancreatic polypeptide (PP) response to a protein meal was measured in 10 healthy volunteers, 10 duodenal ulcer patients, and 6 gastrectomized patients. No significant differences were found between normal and duodenal ulcer subjects, whereas, in gastrectomized patients, basal and food-stimulated plasma PP concentrations were significantly lower (p<0.05). The latter patients, although lacking vagal innervation, showed significantly increased PP levels (p<0.05) 30 min after the beginning of the meal. However, the same secretory pattern related to baseline levels was recorded in all groups: an inverse correlation between basal PP output and stimulated PP output/basal PP output was noted. These results indicate that a humoral mechanism is probably involved in the release of PP, and, furthermore, that neural and paracrine factors may contribute to the regulation of basal and food-stimulated PP concentrations.