AJP - Gastrointestinal and Liver Physiology, Vol 240, Issue 6 459-G465, Copyright © 1981 by American Physiological Society
Cholecystokinin-induced persistent stimulation of enzyme secretion from pancreatic acini
S. M. Collins, S. Abdelmoumene, R. T. Jensen and J. D. Gardner
When pancreatic acini are first incubated with cholecystokinin, washed to
remove free cholecystokinin and then reincubated in fresh incubation
solution, there is significant residual stimulation of amylase secretion.
This residual stimulation requires relatively high concentrations of the
secretagogue, is reversible, and is specific for cholecystokinin. Induction
of residual stimulation occurs more rapidly at 37 degrees C (maximal by 1
min) than at 4 degrees C (maximal by 10 min), and, once induced, residual
stimulation persists for up to 75 min at 37 degrees C and for more than 90
min at 4 degrees C. The persistent effect of cholecystokinin on enzyme
secretion cannot be accounted for by incomplete removal of the secretagogue
by the wash procedure or by activation of some intermediate step in the
mechanism of action of cholecystokinin that persists after the secretagogue
dissociates from its receptors. Instead, cholecystokinin-induced residual
stimulation of enzyme secretion appears to result from persistent
occupation of cholecystokinin receptors by the secretagogue.
