title: The influence of avian pancreatic polypeptide on gastric secretion and motility in laying hens.
abstract: The effects of pancreatic polypeptide (PP) on digestive functions have been studied extensively in mammals. The only two previous studies on the effects of PP on avian (aPP) gastrointestinal function employed bolus injections (i.v.) of the hormone, which may have resulted in nonphysiological plasma levels of aPP. The present study was to determine the effect of aPP infused (iv) at levels simulating postprandial plasma concentrations. Young laying hens were prepared with chronic proventricular and jugular cannulas and with strain gauge transducers sutured to the serosa of the gizzard. In each experiment, a control saline infusion was followed by infusion sufficient to achieve either 7.5 or 15 ng aPP/ml of plasma. Volume, pH, and pepsin content of gastric secretions and frequency and amplitude of gastric contractions were determined. At 15 ng aPP/ml of plasma, secretory volume (P less than .01) and contractile frequency (P less than .001) were significantly depressed as compared to similar data during the saline infusion. At 7.5 ng aPP/ml of plasma, only contractile frequency (P less than .01) was depressed.
mesh_terms: D000818:Animals; D002645:Chickens / Q000502:physiology*; D005260:Female; D005750:Gastric Juice / Q000378:metabolism; D005753:Gastric Mucosa / Q000378:metabolism*; D005769:Gastrointestinal Motility / Q000187:drug effects*; D006863:Hydrogen-Ion Concentration; D007263:Infusions, Parenteral / Q000662:veterinary; D010191:Pancreatic Polypeptide / Q000008:administration & dosage / Q000494:pharmacology*; D010434:Pepsin A / Q000378:metabolism; D013278:Stomach, Avian / Q000187:drug effects*
chemical_list: D010191:Pancreatic Polypeptide; D010434:Pepsin A