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Cholecystokinin-stimulated intracellular signal transduction pathways
1Department of Nutrition, University of North Carolina, Chapel Hill 27599-7400.
The Journal of Nutrition
|August 1, 1994
Summary
Cholecystokinin (CCK) triggers gastrointestinal responses by binding to cell receptors. Intracellular calcium and protein kinase C mediate pancreatic amylase secretion phases differently.
Area of Science:
- Gastroenterology
- Cellular Signaling
- Molecular Biology
Background:
- Cholecystokinin (CCK) is a key hormone regulating diverse gastrointestinal functions.
- CCK initiates physiological effects via plasma membrane receptors on target cells.
- Signal transduction involves intracellular messengers like ions and cyclic nucleotides.
Purpose of the Study:
- To investigate CCK-mediated signal transduction in the exocrine pancreas.
- To examine the roles of calcium and protein kinase C in amylase secretion.
Main Methods:
- Utilized the exocrine pancreas as a model system.
- Analyzed CCK-stimulated calcium mobilization.
- Assessed protein kinase C activation during secretion.
Main Results:
- CCK-stimulated amylase secretion has distinct initial and sustained phases.
- Protein kinase C and intracellular calcium are crucial for the initial secretion phase.
- Extracellular calcium is essential for the sustained phase of amylase secretion.
Conclusions:
- CCK signal transduction pathways are conserved across different tissues.
- Calcium and protein kinase C play differential roles in regulating pancreatic secretion.
- Understanding these pathways is vital for gastrointestinal physiology.
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