(A) Heatmap depicting expression patterns of the most abundantly expressed Kv1, Kv2, Kv3 and Kv4 subunits. Plotting scheme is as Figure 2D.
(B-E) Components of Kv current during the AP of sensory neuron subtypes. Currentwas evoked by AP waveforms (previously recorded in a different cell of each type), and components of current were isolated by sequential cumulative application of 100 nM α-Dendrotoxin (DTX), 100 μM 4-aminopyridine (4-AP), 3 μM AmmTx3, and 100 nM Guangxitoxin-1E (GxTX) to identify Kv1, Kv3, Kv4, and Kv2 currents, respectively. (B’-E’) Currents evoked by a step depolarization to +20 mV (30 ms), applied in parallel with the AP commands in the same cells as B-E.
(F) Stacked bar plots showing the average fraction of total outward K+ current carried by Kv1, Kv2, Kv3, Kv4 channels in Aβ SA1-LTMRs (AP waveform: 31 ± 3% Kv1, 0 ± 1% Kv2, 59 ± 3% Kv3, 7 ± 1% Kv4; Step to +20 mV: 9 ± 2% Kv1, 35 ± 3% Kv2, 22 ± 3% Kv3, 1 ± 1% Kv4; n=15), Aβ RA-LTMRs (AP waveform: 33 ± 4% Kv1, 0 ± 2% Kv2, 58 ± 4% Kv3, 8 ± 2% Kv4; Step to +20 mV: 6 ± 3% Kv1, 45 ± 8% Kv2, 16 ± 7% Kv3, 6 ± 3% Kv4; n=11), MrgD+ nonpeptidergic nociceptors (AP waveform: 20 ± 4% Kv1, 29 ± 6% Kv2, 13 ± 3% Kv3, 37 ± 6% Kv4; Step to +20 mV: 11 ± 3% Kv1, 34 Kv4; n=11; mean ± SEM). Current contributions were quantified by integrating the currents during the AP or the 30ms step depolarization.