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Mechanical Stimulation-induced Calcium Wave Propagation in Cell Monolayers: The Example of Bovine Corneal Endothelial Cells
Published on: July 16, 2013
Gap junction-mediated spontaneous Ca(2+) waves in differentiated cholinergic SN56 cells.
Nishani T Hettiarachchi1, Mark L Dallas, Hugh A Pearson
1Faculty of Medicine and Health, University of Leeds, Leeds LS2 9JT, UK.
Biochemical and Biophysical Research Communications
|June 25, 2010
Summary
Differentiated SN56 cells generate spontaneous calcium (Ca2+) waves via neuronal gap junctions. This finding offers a new system for developing gap junction modulators.
Area of Science:
- Neuroscience
- Cellular Biology
Background:
- Neuronal gap junctions are crucial for intercellular communication but remain less understood than synaptic communication.
- SN56 cells, derived from murine septal neurons, provide a model for studying neuronal communication.
Purpose of the Study:
- To investigate the mechanisms underlying spontaneous calcium (Ca2+) wave generation in differentiated SN56 cells.
- To explore the role of neuronal gap junctions in this process and identify potential modulators.
Main Methods:
- Microfluorimetry was used to detect and analyze Ca2+ waves.
- Patch-clamp electrophysiology recorded cellular currents.
- Polymerase Chain Reaction (PCR) confirmed connexin 36 mRNA expression.
- Pharmacological agents were used to inhibit specific channels and receptors.
Main Results:
- Differentiated SN56 cells spontaneously generated Ca2+ waves, independent of tetrodotoxin but dependent on extracellular Ca2+.
- These waves were not affected by antagonists of NMDA, AMPA/kainate, nicotinic AChR, or purinoceptors.
- Carbenoxolone, halothane, and niflumic acid, known gap junction inhibitors, completely blocked the Ca2+ waves.
- Connexin 36 mRNA was detected, and spontaneous inward currents were inhibited by gap junction blockers.
Conclusions:
- Spontaneous Ca2+ waves in differentiated SN56 cells are propagated by neuronal gap junctions.
- This cellular system is a viable model for the development of novel neuronal gap junction modulators.
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