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Updated: Jun 17, 2026
07:09
The Sciatic Nerve Cuffing Model of Neuropathic Pain in Mice
Published on: July 16, 2014
Targeting primary afferent nerves for novel antitussive therapy
Bradley J Undem1, Michael J Carr
1Asthma and Allergy Center, 5501 Hopkins Bayview Circle, Baltimore, MD 21224, USA. bundem@jhmi.edu
Chest
|January 7, 2010
Summary
Two types of vagal nerves initiate cough reflexes: A-fibers for immediate airway defense and C-fibers for sensations linked to respiratory conditions. Targeting these C-fibers offers novel cough treatment strategies.
Area of Science:
- Neuroscience
- Respiratory Physiology
Background:
- Vagal nerves play a crucial role in initiating cough reflexes.
- Two distinct types of vagal afferent nerves are implicated in cough: A-fibers and C-fibers.
Purpose of the Study:
- To review recent advances in sensory neurobiology for targeting vagal C-fibers.
- To explore novel antitussive (cough-suppressing) therapies.
Main Methods:
- Discussion of two general strategies for targeting vagal C-fibers: decreasing generator potential amplitude and decreasing action-potential discharge efficiency.
- Focus on specific molecular targets including transient receptor potential vanilloid 1 (TRPV1), transient receptor potential A1 (TRPA1), and voltage-gated sodium (Na(V)) channels.
Main Results:
- Vagal A-fibers are rapidly adapting and involved in immediate cough reflexes, crucial for airway defense.
- Vagal C-fibers, when stimulated, evoke cough in conscious animals and produce urge-to-cough sensations in humans, mimicking symptoms of various respiratory diseases.
Conclusions:
- Understanding the distinct roles of vagal A-fibers and C-fibers is key to developing effective cough treatments.
- Targeting vagal C-fiber pathways, particularly TRPV1, TRPA1, and Na(V) channels, presents promising avenues for novel antitussive therapies.
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