background: k+ channel toxins are essential tools for the first purifications, analysis of subunit structures and brain localization of voltage-gated k+ (kv) channels. the effects of a lot of toxins on kv are not fully known. methods: using whole-cell patch clamping technique the action of a series of toxins on kv3.4 current in rat liver cells with expressed kv3.4 channels (rle) cloned cells wa...