Regulation of amylase release from dispersed pancreatic acinar cells.

1. A study has been made of factors influencing release of amylase from dispersed pancreatic acinar cells. 2. In the basal, unstimulated, condition cells released 2-3% of the total amylase present in 30 min. 3. The rate of amylase release was stimulated 50-70% by C-terminal octapeptide of cholecystokinin (CCK-OP, maximally effective concentration, 3 X 10(-10) M); carbamylcholine (maximally effective concentration, 10(-5 M); secretin (maximally effective concentration greater than 10(-6) M); vasoactive intestinal peptide (VIP, maximally effective concentration, 10(-8) M); and adenosine 3':5' monophosphate (cyclic AMP) and guanosine 3':5' monophosphate (cyclic GMP) as well as their dibutyryl derivatives (maximally effective concentrations, 10(-3) M). 4. The responses to CCK-OP or carbamylcholine were potentiated by secretin, VIP or dibutyryl cyclic AMP. 5. The responses to secretin or VIP were potentiated by CCK-OP, carbamylcholine, or dibutyryl cyclic GMP. 6. There appear to be two pathways for the regulation of amylase release from pancreatic acinar cells: one pathway can be stimulated by cholecystokinin or cholinergic agonists, and the response to these stimuli is mediated by cyclic GMP; the other pathway can be stimulated by secretin or VIP, and the response to these stimuli is mediated by cyclic AMP.