The role of regulatory peptides in postnatal metabolic adaptation.

Major changes occur after the umbilical cord is cut at birth in the structure and function of several physiological systems which enable the newborn baby to adapt from an intrauterine milieu of continuous intravenous nutrition via the placenta to a postnatal environment of intermittent enteral feeding with milk. The secretion of regulatory peptides from the gut and pancreas in response to enteral milk feeding may have a fundamental role in initiating and regulating the cascade of developmental changes needed for the utilization of food which occur after birth.