Aspects of gastrointestinal motility in relation to the development of digestive function in neonates

Gastrointestinal motility is responsible for mixing and transport of digesta and elimination of undigested residues. The basis for the motility is the electrical activity of the gastrointestinal smooth muscle, which has a recurring pattern. In the small intestine of mature animals, this pattern is associated with periodic fluctuations of mesenteric blood flow, and gastric, pancreatic and biliary secretion, and with intestinal absorption. In general, feeding disrupts the cyclic pattern in the stomach and small intestine, replacing it with a continuous post-feeding pattern, and the duration of the post-feeding pattern is dependent on animal species, composition of the diet and feeding regime. The perinatal and weaning periods manifest drastic changes in digestive function and, thus, in gastrointestinal motility. Due to difficulties in performing studies in perinatal and neonatal animals, only few data on the development of gastrointestinal motility, and its synchronisation with other digestive functions, are available. Whereas some studies in the literature indicate that the development of gastrointestinal motility follows the maturation of the regulatory mechanisms, recent data also suggest that changes in gastrointestinal motility around birth and weaning reflect changes in nutrient supply. This paper deals with some aspects of gastrointestinal motility, primarily in the gastric antrum and small intestine, of neonatal animals. Certainly, changes in gastrointestinal motility in early life could be of paramount importance for proper digestive function and this research area requires further attention. (C) 2000 Elsevier Science B.V. All lights reserved.