Effects of porcine gastric fundic factor, somatostatin, substance P, glucagon, neurotensin, bombesin, VIP, motilin, and pentagastrin on jejunal glucose absorption in the rat.

The effects of a porcine gastric fundic mucosal extract (molecular weight less than 10 000) has been compared with the effects of eight candidate gastrointestinal peptides on glucose absorption from the jejunum in a rat model. Bolus injection of the extract produced immediate and marked depression of glucose absorption. None of the candidate peptides tested produced this response, although somatostatin and substance P depressed absorption as a late phenomenon after 30 minutes. We conclude that the effects of the fundic extract are not reproduced by any of these candidate peptides. This strengthens the evidence for a novel gastrointestinal peptide, resident in fundic mucosa, which affects absorption from upper small bowel.