Effects of ginseng-spikenard heart-nourishing capsule on inactivation of C-type Kv1.4 potassium channel.

This research is to explore the effects of traditional Chinese medicine Ginseng-spikenard heart-nourishing capsule on the inactivation of c-type Kv1.4 channels (Kv1.4∆N) in Xenopus laevis oocytes with two-electrode voltageclamp technique. Defolliculated oocytes (stage V-VI) were injected with transcribed cRNAs of ferret Kv1.4δN channels. During recording, oocytes were continuously perfused with ND96 solution (control group) and solution prepared from Ginseng-spikenard heart-nourishing capsule (experimental group). Results found that, at the command potential of +50 mV, the current of experimental group was reduced to 48.33±4.0% of that in control group. The inactivation time constants in control and experimental groups were 2962.56±175.35 ms and 304.13±36.22ms, respectively (P<0.05, n=7). The recovery time of fKv1.4∆N channel after inactivation in control group and experimental groups was 987±68.39 ms and 1734.15±98.45 ms, respectively (P<0.05, n=5). Ginseng-spikenard heart-nourishing capsule can inhibit the Kv1.4δN channel, which may be one of the mechanisms of underlying antiarrhythmia.