Impaired Pancreatic Innervation after Pyloric Transsection in Dogs: Reduced Pancreatic Polypeptide Response to Insulin Hypoglycaemia

Pancreatic polypeptide (PP) is released by efferent vagal impulses and its secretion is impaired after truncal and selective gastric vagotomy while remaining unchanged after parietal cell vagotomy. In three dogs an innervated antral pouch with trans-section of the pylorus was constructed. After this operation the PP response to insulin hypoglycaemia was significantly reduced as compared to the preoperative response. In another four dogs an innervated antral pouch was constructed without transsecting the pylorus. Postoperatively we found that the PP response to insulin hypoglycaemia was unchanged compared to preoperatively. These results seem to indicate that vagal fibres to the pancreas run in close anatomic relation to the pylorus, and their inevitable damage during pyloric transsection results in reduced endocrine pancreatic secretion to vagal stimuli.