Electrophysiology protocols.

<p><b>a</b>. CGRP⁺ neurons (red; marked with blue arrow) selected for recording were classified by size (C_m in pF) and staining with IB4 (green; marked with yellow arrow). <b>b</b>. Stimulus waveform (1nA, 0.5 msec) indicated below trace generated a single AP in small DRG neuron. We analyzed AP and AHP parameters: resting membrane potential–V_m; duration at base–dB and the time required for the AHP (measured in mV) to decay by 80%—(AHP₈₀). In addition, we measured rise time (RT) and fall time (FT) of AP (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0198601#pone.0198601.t001" target="_blank">Table 1</a>). Characteristic AP “hump” is indicated by black arrow. <b>c</b>. Outward current was generated by the indicated waveforms found below traces. The decay constant τ was derived from standard single exponential fits between points indicated by arrows for the final outward current trace (+20 mV). Characteristic “spike-like” peak is shown by arrow on trace generated by stepping to +0 mV.