Jme. Knapper et al., PLASMA AND INTESTINAL CONCENTRATIONS OF GIP AND GLP1(7-36)AMIDE DURING SUCKLING AND AFTER WEANING IN PIGS, Hormone and Metabolic Research, 27(11), 1995, pp. 485-490
Plasma concentrations of glucose dependent insulinotropic polypeptide
(GIP) and glucagon-like peptide-1(7-36)amide (GLP-1[7-36]amide) were m
easured after milk ingestion in 16 - 18 day old piglets and after wean
ing diet ingestion in 33 day old piglets weaned at 21 days. Intestinal
concentrations of these two hormones were also measured in unsuckled
piglets of less than 24h of age, and piglets whose ages corresponded w
ith those used for plasma measurements. Suckling piglets showed a mode
rate glycaemic and insulinaemic response to milk ingestion. Plasma GIP
and GLP-1(7-36)amide levels were significantly elevated at 1 and 3-h
post-prandially. Weaned piglets showed a much more marked glucose and
insulin response to meal ingestion. Plasma GIP and GLP-1(7-36)amide le
vels were again significantly elevated at 1 and 3h in these animals. T
he mean plasma GIP response was greater in the weaned animals compared
with the suckling animals at the time points investigated. The plasma
GLP-1(7-36)amide response in contrast was significantly greater at 1h
in the suckling animals. In comparison, GIP concentrations in acid et
hanol extracts of the small intestine were significantly higher during
suckling and GLP-1(7-36)amide concentrations significantly higher aft
er weaning. The circulating levels of both hormones seen during suckli
ng and after weaning were far higher than those previously reported in
humans. We conclude that both milk ingestion and the weaning diet are
capable of stimulating CIP and GLP-1(7-36)amide in piglets and sugges
t that the levels of both hormones seen in this study may be important
in adipose tissue metabolism at this time.