Abstract
The effects of Ca++ on release of amylase by mouse pancreas in vitro were studied. The cholinergic agonist bethanechol increased release of amylase in a parallel manner in both normal and O Ca++ medium; however, release at all concentrations of bethanechol was depressed about 50% in O Ca++ medium. When pancreatic fragments were superfused with O Ca++ medium, bethanechol still produced a normal stimulation of amylase release after half of the total tissue Ca++ was washed out. This Ca++ loss included both extracellular and some intracellular Ca++. Uptake and equilibration of 45Ca++ into pancreatic fragments was multiphasic, with total equilibration with stable Ca++ still not reached after 3 hr. Addition of bethanechol had no effect on the rate of 45Ca uptake and equilibration. 45Ca++ efflux was not influenced by superfusion in O Ca++ medium, while the stimulation of 45Ca++ efflux by bethanechol was enhanced. It is concluded that extracellular Ca++ and/or Ca++ influx is not of major importance in triggering pancreatic enzyme release, but that extracellular Ca++ may regulate the release process thus accounting for the parallel changes in unstimulated and stimulated amylase release.
| Original language | English (US) |
|---|---|
| Title of host publication | American Journal of Physiology |
| Pages | 1729-1732 |
| Number of pages | 4 |
| Volume | 228 |
| Edition | 6 |
| State | Published - 1975 |
| Externally published | Yes |
ASJC Scopus subject areas
- Medicine(all)