1 International Institute for Infant Nutrition and Gastrointestinal Disease, Department of Pediatrics, Mount Scopus, Hadassah-Hebrew University Medical, Center, Jerusalem, ISRAEL
The Koenig et al study1 showed different effects of two-thirds concentration feeding compared with one-third concentration in relation to shorter mean time of onset and longer duration of fed response. The different motility response can be related to availability of regulatory mechanisms. Similar studies of individual food component,26 eg, glucose, triglyceride, and casein hydrolysate, disrupted fasting activity but had differing effects on the duration of fed activity and the increase of contractile activity. Glucose followed by peptides then lipids caused the greatest increase in contraction and duration of fed activity.26 It is assumed that each group of nutrients induces the secretion of different peptide hormones that may be responsible for the fed pattern of motility. It is suggested that the feeding releases gastrin and cholecystokinin27 that in return change the pattern of motility activity to the fed pattern. When a protein feeding was given intraduodenally both cholecystokinin and pancreatic polypeptide were released in large quantities and the intestinal motility changed to fed pattern.27 Peptide YY is also released in large quantities after both a large protein and fatty meal.28 The main question that the Koenig et al study1 raises is how the concentration, volume, and presence of the feed in the stomach or duodenum affect the release of regulatory gut peptides and gastrointestinal hormones. In addition it is important to know how the ontogeny of gut hormones and regulatory peptide can be manipulated by changing the mode, content, concentration, and volume of feeding.
Available fat, carbohydrate, and protein in the premature diet might be important in modifying the developmental pattern of intestinal and pancreatic enzymes as well as affecting gastric emptying.