Cholecystokinin-induced phosphatidylinositol hydrolysis in rat pancreatic acinar cells: modulation by extracellular calcium and manganese.

  title={Cholecystokinin-induced phosphatidylinositol hydrolysis in rat pancreatic acinar cells: modulation by extracellular calcium and manganese.},
  author={Murray Korc and Bysani Chandrasekar and Steven A. Siwik},
  volume={129 1},
The role of extracellular calcium in modulating the actions of cholecystokinin octapeptide (CCK8) on phosphatidylinositol 4,5-bisphosphate hydrolysis was studied in freshly isolated rat pancreatic acini and cultured AR42J cells. In both cell types, CCK8 rapidly induced the formation of inositol 1,4,5-trisphosphate [Ins(1,4,5)P3] and 1,3,4, 5-tetrakisphosphate [Ins(1,3,4,5)P4]. The actions of CCK8 were inhibited by lanthanum and manganese, agents that block transmembrane calcium fluxes, and by… 
5 Citations

Carbachol and Cholecystokinin Enhance Accumulation of Nicotine in Rat Pancreatic Acinar Cells

The increasing effects of carbachol and cholecystokinin on the accumulation of nicotine may explain, at least in part, the mechanisms involved in the multiplicative effects of the combination of two risk factors, smoking habit and high-fat or high-protein diets, on human pancreatic diseases.

Secretin potentiates cholecystokinin‐stimulated amylase release by AR4‐2J cells via a stimulation of phospholipase C

It is shown that cholecystokinin (CCK) induces amylase secretion from AR4‐2J pancreatic acinar cells via stimulation of PLC activity and secretin potentiated the acinar cell secretory response to CCK by cAMP‐mediated cross‐talk with the PLC signal transduction pathway.

Induction of Ca2+ transport in liposomes by insulin.

Metal ion binding affinities of gastrin and CCK in membrane mimetic environments

  • J. LutzE. WeyherL. Moroder
  • Chemistry, Biology
    Journal of peptide science : an official publication of the European Peptide Society
  • 1995
The significantly higher affinity of lanthanide ions than Ca2+ for the peptides could well play a role in the inhibibitory activity of Lanthanum on the signal transduction of the CCK family of hormones.

On the Mechanism of Hormone Recognition and Binding by the CCK‐B/Gastrin Receptor

  • L. Moroder
  • Biology
    Journal of peptide science : an official publication of the European Peptide Society
  • 1997
The observed receptor interaction of the deliberately membrane‐anchored gastrin offers interesting constraints for computational docking experiments on a modelled CCK‐B/gastrin receptor by additionally taking into account information derived from mutagenesis studies.



Role of calcium in cholecystokinin-stimulated phosphoinositide breakdown in exocrine pancreas.

In dispersed acini from guinea pig pancreas cholecystokinin octapeptide (CCK-OP) stimulated breakdown of the phosphoinositides phosphatidylinositol (PI) and its phosphorylated derivative,

Rapid mobilization of Ca2+ from rat insulinoma microsomes by inositol-1,4,5-trisphosphate

It is shown directly that Ins1,4,5P3 rapidly releases Ca2+ from a microsomal fraction of rat insulinoma but not from mitochondria or secretory granules, suggesting that Ins2+ mobilization from internal pools is not mediated.

Effect of lanthanum on pancreatic protein synthesis in streptozotocin-diabetic rats.

  • M. Korc
  • Biology, Chemistry
    The American journal of physiology
  • 1983
It is suggested that CCK and other pancreatic secretagogues that act via Ca2+ enhance protein synthesis by increasing cell membrane permeability to Ca2- and provide additional evidence that this may be an important mechanism by which CCK regulates pancreatic exocrine function.

Modulation of cytosolic free calcium levels by extracellular phosphate and lanthanum.

  • M. KorcM. Schöni
  • Biology
    Proceedings of the National Academy of Sciences of the United States of America
  • 1987
It is suggested that extracellular phosphate may modulate resting [Ca2+]i levels in pancreatic acini and other cell types and that mobilization of intracellular Ca2+ may partly depend on the availability of a lanthanum-sensitive pool of cell-surface Ca2+, that is not readily removed by EGTA.

Ion channels activated by inositol 1,4,5-trisphosphate in plasma membrane of human T-lymphocytes

It is suggested that Ins(1,4,5)P3 acts as the second messenger mediating transmembrane Ca2+ influx through specific Ca2-permeable channels in mitogen-stimulated T-cell activation.

Quin 2 and Manganese Define Multiple Alterations in Cellular Calcium Homeostasis in Diabetic Rat Pancreas

The findings suggest that insulin deficiency is associated with multiple alterations in Ca2+ homeostasis in the pancreatic acinar cell, which include a decrease in basal levels, perturbations in the signal transduction system that mediates the rapid mobilization of [Ca2+]i after CCK-8–receptor binding, and enhanced sensitivity to the actions of manganese on intracellular Ca 2+ pools.

Synergism of inositol trisphosphate and tetrakisphosphate in activating Ca2+-dependent K+ channels

It is shown that neither Ins P3 alone nor Ins P4 alone can activate a sustained current, whereas inositol 1,3,4,5-tetrakisphosphate in combination in combination evoke a sustained increase in Ca2+-activated K+ current which is dependent on external Ca2+.