Fig. 4.

Ppr-induced LTH involves potentiation of DSFs. A, magnification of the representative 10-second trace of a Ppr-treated sensory neuron recorded at −45 mV shown in Fig. 1D (right side). APs are clipped to show details of the fluctuations of membrane potential. Red arrow indicates the largest subthreshold DSF that was used as a conservative estimate of AP voltage threshold (represented by red dashed line). B-C, effect of Ppr and of each inhibitor tested on DSF amplitude (B) or the frequencies of large (≥5 mV) DSFs (C). Data are graphed as medians. Each open circle represents the mean DSF value from a single neuron. Comparisons of amplitudes or large DSF frequencies between Ppr and vehicle or each Ppr with inhibitor used Kruskal-Wallis followed by Dunn’s multiple comparisons tests, as were differences between vehicle and each inhibitor alone. p values are reported in each panel and p < 0.05 was considered significant. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)