Gut hormones and the first meals.

TABLE 1. Circulating hormones ofthe gut which were not seen in animals deprived of enteral feeding. In addition, oral feeding has been demonstrated to enhance gut enzyme activity (jejunal lactase and acid phosphatase) in newborn piglets (Widdowson et al., 1976) and may initiate important changes in intermediary metabolism for example the increased responsiveness of'pancreatic p-cells to glucose seen in enterally fed newborn piglets (Gentz, Persson, Kellum, Bengtsson & Thorell, 1971) and rats (Asplund, 1972). If feeding is a key factor in inducing adaptive events which equip the newborn infant for postnatal nutrition, then what is the mechanism? Evidence is accumulating that supports the hypothesis that gut hormones may play a key role in this process. Studies in animals and adult man demonstrate that these hormones can induce some of the changes which are known to occur after birth in normally fed neonates. Thus gastrin (Johnson, 1976, 1977) and enteroglucagon (Gleeson, Bloom, Polak, Henry & Dowling, 1971; Besterman, Sarson, Blackburn, Cleary, Pilkington & Bloom, 1978a; Beste~man, Bloom, Adrian, Christofides, Sarson, Mallinson,