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Updated: Jul 12, 2026
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Homogeneous Time-resolved Förster Resonance Energy Transfer-based Assay for Detection of Insulin Secretion
Published on: May 10, 2018
Rapid and reversible secretion changes during uncoupling of rat insulin-producing cells
1Department of Morphology, University of Geneva Medical School, Switzerland.
The Journal of Clinical Investigation
|September 1, 1990
Summary
Heptanol blocks gap junctions between insulin-producing B cells, disrupting glucose-stimulated insulin secretion. This effect is reversible and highlights the role of cell-to-cell communication in regulating insulin release.
Area of Science:
- Endocrinology
- Cell Biology
- Metabolic Research
Background:
- Insulin secretion by pancreatic B cells is crucial for glucose homeostasis.
- Cell-to-cell communication through gap junctions is suspected to play a role in B cell function.
Purpose of the Study:
- To investigate the impact of gap junction blockade on insulin secretion.
- To elucidate the mechanism by which gap junctions influence B cell secretory responses.
Main Methods:
- Utilized heptanol, a gap junction blocker, on rat pancreatic islets and RINm5F cells.
- Assessed insulin secretion in response to glucose and D-glyceraldehyde.
- Examined intracellular pH and Ca2+ levels, and secretion pathway steps.
Main Results:
- Heptanol rapidly blocked gap junctions and abolished glucose-stimulated insulin secretion in intact islets.
- The inhibitory effect was reversible upon removal of heptanol.
- Heptanol inhibited insulin secretion in B cell pairs but not single cells, and did not affect intracellular signaling pathways.
Conclusions:
- Junctional coupling between B cells is essential for normal glucose-stimulated insulin secretion.
- Gap junction communication regulates insulin release in a cell contact-dependent manner.
- The mechanism involves coordinated B cell activity rather than direct effects on the secretory machinery.
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