Enhancement of potassium currents in rat dorsal root ganglion neurons by sulfur dioxide derivatives
二氧化硫衍生物对大鼠背根神经元瞬间外向钾电流和延迟整流钾电流的影响

This study addressed the effect of sulfur dioxide (SO2) derivatives on transient outward potassium currents (IA and ID) and delayed rectifier current (IK) in somatic membrane of freshly isolated rat dorsal root ganglion neurons using the whole cell configuration of patch-clamp technique. SO2 derivatives reversibly increased the amplitudes of potassium currents in a concentration-dependent and voltage-dependent. SO2 derivatives significantly shifted the activation of delayed rectifier potassium current in the hyperpolarizing direction and shifted the inactivation curve of transient outward potassium currents in the depolarizing direction. Parameters for the fit of a Boltzmann equation to mean values for delayed rectifier current activation were V1/2=20.3±2.1 mV before and 15.0±1.5 mV after application 10 μM SO2 derivatives. The half inactivation of IA was shifted 6 mV and ID 7.4 mV after application 10 μM SO2 derivatives. These results indicated that SO2 derivatives increased the amplitudes of potassium currents and changed the properties of potassium channels.