PEPTIDE YY AUGMENTS POSTPRANDIAL SMALL-INTESTINAL ABSORPTION IN THE CONSCIOUS DOG

Since feeding increases intestinal fluid and electrolyte losses in sho rt bowel syndrome, an agent increasing postprandial small bowel absorp tion might have a therapeutic role. Peptide YY (PYY) has recently been shown to increase net small bowel absorption under basal conditions. The aim of this study was to determine whether PYY can also augment po stprandial absorption. Exteriorized, neurovascularly intact jejunal an d deal segments (25 cm Thiry-Vella loops) were created in dogs (n = 6) and gastrointestinal continuity was restored. Luminal perfusion with [C-14]polyethylene glycol was used to calculate the change in water (H 2O) and sodium (Na+) and chlorine (Cl-) ion fluxes after an oral meal. Changes in fluxes were also determined after a 2-hour infusion of a p hysiological dose of PYY (100 pmol/kg per hour). In a third series of experiments, fluxes were measured after a meal, during PW infusion. Fe eding increased small bowel absorption of fluid and electrolytes indep endent of the luminal content. This effect persisted for 2 hours after the meal. PYY infusion significantly augmented this proabsorptive res ponse in both jejunum and ileum. These results suggest that PYY-agonis ts may have a therapeutic role in conditions such as short bowel syndr ome where postprandial absorption is reduced.