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Updated: Apr 21, 2026
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Visualizing Axonal Growth Cone Collapse and Early Amyloid β Effects in Cultured Mouse Neurons
Published on: October 30, 2018
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Axonal excitability in primary amyloidotic neuropathy
Jessica Hafner1, Roula Ghaoui, Luke Coyle
1Department of Neurology and Clinical Neurophysiology, Royal North Shore Hospital, Reserve Road, St Leonards, New South Wales, 2065, Australia.
Muscle & Nerve
|November 11, 2014
Summary
Amyloid neuropathy does not alter axonal membrane potential, suggesting ischemia and compression are not primary causes. This finding helps understand peripheral nerve damage in amyloidosis.
Area of Science:
- Neurology
- Neurophysiology
Background:
- Amyloidosis, both acquired and hereditary, can lead to peripheral neuropathy.
- The precise mechanisms underlying amyloid-related neuropathy remain unclear.
- Threshold tracking techniques offer in vivo assessment of axonal membrane properties.
Purpose of the Study:
- To investigate the pathogenetic mechanisms of peripheral neuropathy in primary amyloidosis.
- To assess axonal excitability using quantitative testing in patients with amyloidosis.
Main Methods:
- Studied 10 subjects with primary amyloidosis.
- Utilized conventional nerve conduction studies.
- Performed quantitative sensory, autonomic, and axonal excitability testing on median nerve fibers.
Main Results:
- Subjects exhibited small- and large-fiber neuropathy on conventional testing.
- No significant differences in axonal excitability were observed between subjects and controls.
- A difference was noted only in the stimulus required to activate sensory fibers.
Conclusions:
- Amyloid-related neuropathy does not involve primary or secondary changes in membrane potential.
- Ischemia and axonal compression are unlikely mechanisms for this type of neuropathy.
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