Supplementary Figure 5: Time course of serotonin modulation of Ih.
From: Serotonin modulates spike probability in the axon initial segment through HCN channels
(a) Voltage dependence of Ih activation in whole-cell voltage-clamp recordings (voltage steps: −30 mV to −110 mV in −10 mV steps, 1 s duration). Decreased Ih after bath application of 20 µM 5-HT shows extensive recovery after washout (black traces). b. Time course of Ih during 5-HT application (red). Instantaneous leak current remains relatively stable (gray). (a), (b), and (c) indicate time points of example traces in a. (c) Time course of changes in half-activation voltage of Ih. (d) Normalized conductance plots of V1/2 for the time points shown in b and c, while instantaneous leak current (gray) is constant. (e) Quantification of group data for the change in maximum current and V1/2 for Ih in 20 µM 5-HT and washout conditions relative to control (red bars). The amplitude of Ih but not instantaneous leak current differs significantly from the 5-HT condition (current amplitude: Ih, p = 0.029, instantaneous leak, p=0.73; Ih V1/2, p=0.017 (n=3). 2-tailed paired t test. Error bars indicate SEM. * p<0.05
