Comparison of the effects of antiarrhythmic drugs flecainide and verapamil on fKv1.4ΔN channel currents in Xenopus oocytes.

ABSTRACT:

Aim

To study the effects of Na(+) channel blocker flecainide and L-type Ca(2+) channel antagonist verapamil on the voltage-gated fKv1.4ΔN channel, an N-terminal-deleted mutant of the ferret Kv1.4 K(+) channel.

Methods

fKv1.4ΔN channels were stably expressed in Xenopus oocytes. The K(+) currents were recorded using a two-electrode voltage-clamp technique. The drugs were administered through superfusion.

Results

fKv1.4ΔN currents displayed slow inactivation, with a half-inactivation potential of -41.74 mV and a slow recovery from inactivation (τ=1.90 s at -90 mV). Flecainide and verapamil blocked the currents with IC(50) values of 512.29 ± 56.92 and 260.71 ± 18.50 μmol/L, respectively. The blocking action of the drugs showed opposite voltage-dependence: it was enhanced

SUBMITTER: Chen H 

PROVIDER: S-EPMC4011620 | biostudies-literature | 2013 Feb

REPOSITORIES: biostudies-literature