Fig. 3.
Crizotinib inhibits funny current (If) in mouse sinoatrial node cells. The whole-cell patch clamp technique was used to measure the effects of crizotinib on If in isolated mouse sinoatrial node cells. a Representative tracing showing steady-state If over time (min) before (a) and during (b) perfusion of crizotinib (crizo, 1 μmol/L), after washout of crizotinib (c) and after addition of 2 mmol/L CsCl (d). Cell membrane potential was held at -35 mV, and If was elicited by a step to -115 mV for 2 s then return to holding potential (inset, panel b). Currents were normalized to membrane capacitance (pA/pF). b Representative single If tracings before (CTL), during perfusion with crizotinib (crizo), after washout of crizotinib (washout), and after addition of 2 mmol/L CsCl (Cs), corresponding to a-d in panel A. c Group mean values of If current expressed as % of control before (CTL) and after crizotinib (crizo, 1 μmol/L) (n = 6 for each group, *, p < 0.05)