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Updated: Aug 11, 2026
10:46
Mechanical Stimulation-induced Calcium Wave Propagation in Cell Monolayers: The Example of Bovine Corneal Endothelial Cells
Published on: July 16, 2013
Calcium ions trigger the expansion in bistable myelin
Neuroscience Letters
|January 14, 1987
Summary
Nerve myelin can transition from compact to expanded states, triggered by calcium ions (Ca). This expansion, occurring in aqueous spaces, may play roles in normal nerve function and myelin breakdown.
Area of Science:
- Neuroscience
- Biochemistry
- Cell Biology
Background:
- Traditional ultrastructural studies of nerve myelin focus on static properties.
- Emerging research suggests myelin's dynamic potential for supramolecular transitions.
Purpose of the Study:
- To investigate the dynamic transition of myelin from a compact to an expanded form.
- To identify the trigger and mechanism of myelin expansion.
- To explore the physiological implications of myelin expansion.
Main Methods:
- Ultrastructural imaging of myelin multilayers.
- Physiological manipulation of calcium ion (Ca) levels in teleost specimens.
- Transfer of excised myelin specimens between Ca-containing and Ca-free media.
Main Results:
- Myelin expansion involves a 27 Å thickening of the membrane pair in teleosts.
- Physiological levels of Ca trigger the myelin expansion.
- Myelin expansion occurs within the aqueous spaces between lipid bilayers.
- Partial expansion can be maintained by controlling Ca levels.
Conclusions:
- Myelin's ability to transition to an expanded form is calcium-dependent.
- Local myelin expansion may occur during normal nerve function.
- Widespread myelin expansion could be an early indicator of myelin breakdown in vivo.
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