Gastroenterology
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To determine if carbohydrates perfused into the ileum affect gastric emptying and circulating levels of gastrointestinal hormones, 18 healthy subjects were intubated with an oroileal tube. A 400-cal (60% carbohydrate, 20% protein, 20% fat) homogenized meal labeled with 111In-DTPA was then infused into the stomach over 10 min. Simultaneously, a test solution of normal saline (n = 6) or 12.5 (n = 4), 25 (n = 4), 50 (n = 2), or 100 (n = 2) mg/min of carbohydrates (75% rice starch, 25% glucose) containing a nonabsorbable marker, polyethylene glycol, was continuously perfused into the terminal ileum at 3 ml/min for 7 h. ⋯ Plasma concentrations of C-peptide, glucagon, motilin, gastrin, and human pancreatic polypeptide were not related to gastric emptying or ileal perfusates, but decreased concentrations of gastric inhibitory polypeptide and neurotensin and increased concentrations of peptide YY were significantly associated (p less than 0.05) with slowing of gastric emptying. Perfusing carbohydrates into the ileum was associated with nausea, abdominal pain, and vomiting, but we could detect no direct relationship between the onset of these symptoms and gastric emptying. Slowing of gastric emptying of a homogenized mixed meal by the entry of complex carbohydrates into the ileum may be partly mediated by peptide YY or nonvagally mediated neural mechanisms.