Different role of TTX‐sensitive voltage‐gated sodium channel (NaV1) subtypes in action potential initiation and conduction in vagal airway nociceptors

摘要

Key points class="unordered" style="list-style-type:disc" id="tjp12857-list-0001">The action potential initiation in the nerve terminals and its subsequent conduction along the axons of afferent nerves are not necessarily dependent on the same voltage‐gated sodium channel (NaV1) subunits.The action potential initiation in jugular C‐fibres within airway tissues is not blocked by TTX; nonetheless, conduction of action potentials along the vagal axons of these nerves is often dependent on TTX‐sensitive channels.This is not the case for nodose airway Aδ‐fibres and C‐fibres, where both action potential initiation and conduction is abolished by TTX or selective NaV1.7 blockers.The difference between the initiation of action potentials within the airways vs. conduction along the axons should be considered when developing NaV1 blocking drugs for topical application to the respiratory tract.