Figure 4
Robust I h deactivation kinetics at P0. (A) Examples of Ih deactivations at −65 mV from a preceding activation step of −130 mV and corresponding single exponential fits at P0 under varying conditions. The course of Ih deactivation did not change when intracellular modulators (+ cAMP or + U73122) were included or extracellular Ca2+ omitted (0 Ca2+). Symbols correspond to the coding in (B). (B) Deactivation time constants were not changed after experimental alterations of intracellular cAMP (100 μM, grey-filled circles), omitting extracellular Ca2+ (black-filled circles), or by adding the intracellular PLC blocker U73122 (open squares) compared to native P0 conditions (open grey circles). Data are presented with 25 to 75% box plots (left of respective data). The mean for each condition is indicated by a line comprising the box and individual data points.