Modulation of Human Periodic Interdigestive Gastrointestinal Motor and Pancreatic Function by the Ileum

Abstract

Following ingestion of a meal, unabsorbed nutrients may reach the distal intestine partly after the termination of the prandial period, i.e., in the presence of interdigestive motor and secretory patterns. To determine if interdigestive motility and pancreatic enzyme secretion are modulated by the delivery of nutrient into the ileal lumen, six fasting volunteers were intubated with an oroileal multilumen tube system that permitted multiple small intestinal manometry, gastric and duodenal aspiration, and perfusions of marker and test solutions. Ileal perfusions of nutrient or saline solutions were started during phase I of the interdigestive motility cycle. Ileal perfusion with carbohydrate or lipids increased the duration of motor quiescence and decreased the length of the interdigestive cycle, mainly by decreasing the proportion of phase I1 activity compared with ileal saline (p < 0.01).Pancreatic outputs of amylase, trypsin, and chymotrypsin prior to ileal perfusions were low because, due to the protocol, perfusions were started during phase I. With ileal saline, enzyme outputs increased (p < 0.05) in association with the occurrence of phase I1 motility, as expected. By contrast, ileal carbohydrate and triglyceride perfusion prevented the phase 11-associated increase in enzyme outputs (p < 0.05). The data suggest that the presence of nutrients within the ileal lumen may modulate interdigestive motor and pancreatic functions.

Effect of ileal fat perfusion on satiety and hormone release in healthy volunteers

“…22 A function of the ileal brake in the physiological regulation of gastrointestinal motility and secretion has been proposed. 23 The effect of lipids administered into the small intestine on satiety and food intake in humans has been studied previously by Welch et al 8,12 These authors demonstrated that infusion of fat in the ileum caused a reduction in food intake in healthy volunteers.…”

Pancreatic exocrine insufficiency in pancreatic cancer: A review of the literature

“…In this context, ileal lipid perfusion in 12 healthy volunteers resulted in dose-dependent inhibition of both pancreatic enzyme and bile secretion with unchanged intestinal motor activity [7,11,12].…”

Human pancreatic exocrine response to nutrients in health and disease

“…These peptides are released from the distal intestinal mucosa in response to a meal or intraileal nutrients (fig 4). 20 62-66 Ileal perfusion of lipids inhibits secretory and motor functions of upper gastrointestinal organs both in the interdigestive state 67 and during weak or moderate endogenous stimulation ( fig 5). 17 68-72 In addition, there are several studies suggesting comparable inhibitory effects of 12 60-100 26 42 51 -150 12 Data are derived from studies using test meals with 300-600 kcal and using no or only low marker perfusion rates ((3 ml/min).…”