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Updated: Jul 28, 2026
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Published on: May 8, 2014
Supramolecular aggregation and organization in peripheral nerve myelin
Journal of Ultrastructure Research
|September 1, 1983
Summary
Glutaraldehyde fixation reveals lipid bilayer compartmentalization in myelin, suggesting a domain structure around transmembrane proteins. This organization is visualized using specific preparation and staining techniques.
Area of Science:
- Neuroscience
- Biochemistry
- Cell Biology
Background:
- Myelin's lipid bilayer structure is crucial for nerve impulse conduction.
- The precise arrangement of lipids and proteins within myelin is not fully understood.
Purpose of the Study:
- To investigate the supramolecular organization of lipids within glutaraldehyde-fixed peripheral nerve system (PNS) myelin.
- To determine if myelin lipid bilayers exhibit compartmentalization and domain formation.
Main Methods:
- Transmission electron microscopy of negatively stained myelin sections.
- Varied fixation techniques including glutaraldehyde, glutaraldehyde-urea, and tannic acid.
- Lipid extraction and cadmium ion treatment.
Main Results:
- Myelin lipid bilayers show marked compartmentalization under specific preparative conditions.
- This compartmentalization is centered around transmembrane P0 proteins, surrounded by immobilized phospholipid annuli.
- Lipid domains exhibit nonrandom distribution within lamellar planes.
- Visualization is dependent on specific staining and embedding methods, with lipid extraction and surface tension aiding observation.
Conclusions:
- Myelin's lipid bilayers possess a supramolecular domain pattern.
- Transmembrane proteins play a key role in organizing lipid arrangements.
- Specific preparative methods are essential for visualizing myelin's intricate lipid organization.
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