Stability of pancreatic enzyme activities in duodenal juice after pancreatic stimulation by a test meal or exogenous hormones.

The activities of pancreatic lipase, pancreatic amylase, and trypsin were followed after storage at -20 degrees C in duodenal juices collected after pancreatic stimulation by either a test meal or exogenous hormones. The activities of all three enzymes were stable for up to one year in juices collected after a test meal. However, in nine out of 10 hormonally stimulated juices, lipase activities fell to less than 50% of the initial activity within three weeks of storage, and in a third, trypsin activities fell to less than 60% over a similar period. Amylase activity remained relatively unchanged. The in-vitro addition of the test meal, its separate components, or glycerol (50%, V/V) stabilised lipase and trypsin activities in hormonally stimulated juices stored at -20 degrees C for at least one month.