Fig. 1.
Muscle afferent neurons express nicotinic ACh receptors (nAChRs). A–C: example currents recorded from muscle afferent neurons in response to 100 μM ATP (A), 10 μM capsaicin (CAP; B), and 1 mM ACh (C). The application of each agonist is indicated by the horizontal bar above each trace. D–F: the percentage of responsive neurons is shown for 3 groups, which are all muscle afferent neurons tested (D; n = 52), neurons expressing TTX-resistant voltage-dependent sodium (NaV) current (E; n = 45), and neurons expressing TTX-sensitive NaV current (F; n = 7). “None” indicates muscle afferent neurons that failed to respond to any of the 4 applied activators. The agonist concentrations are listed above. AITC, allyl isothiocyanate.