A surgical and experimental procedure was developed to enable the coll
ection of pure and inactivated pancreatic juice during the growth of t
he pig. Studies have shown that, during the suckling period, both the
basal and the secretory responses to suckling are low, if present at a
ll. After weaning, basal levels of the total exocrine secretion, total
protein, amylase, and trypsin, respectively, increase slightly, while
the postprandial levels of total protein, amylase, trypsin, lipase, c
olipase, and carboxylester lipase, respectively, increase markedly. Th
e pancreatic juice enzyme composition changes qualitatively and the an
tibacterial activity of the pancreatic juice also significantly increa
ses. Piglet age appeared to be of minor importance, since weaning at e
ither 4 or 6 wk of age gave the same results. Secretin and CCK adminis
tered together in supraphysiological doses only significantly affect e
xocrine function from 3-4 wk of age. However, CCK may also affect the
exocrine pancreas indirectly via reflexes initiated intraduodenally. M
ilk consumption in the suckling pig leads to a postprandial increase i
n glucose levels but not insulin. Milk appears to be able to regulate
the exocrine pancreas to produce only the amount and type of enzymes r
equired for digestion. Thus, milk components or digestive products may
affect pancreas function regulation. Studies show that enterostatin,
the procolipase activation peptide, may inhibit pancreatic secretion m
ediated indirectly through the GI tract. Pancreastatin, an endocrine p
eptide, inhibits both insulin secretion and protein and trypsin secret
ion to pancreatic juice. In hypoinsulinemic (alloxan + streptozotocin
diabetes) pigs (15-20 kg), no postprandial pancreatic juice response i
s seen, although CCK 33 + secretin can stimulate pancreatic secretion.
Hypoinsulinemic pigs have a reduced capacity for glucose tissue utili
zation, suggesting that tissue metabolism and exocrine pancreas secret
ion are related.