[Retracted] Ginsenoside Rg3 Alleviates Antithyroid Cancer Drug Vandetanib-Induced QT Interval Prolongation

Figure 7

The development of vandetanib block of hERG channels was further assessed using an envelope of tail test in HEK293 cells. (a, b) Envelope tail protocol and representative hERG current before (control) and after application of 2 μM vandetanib. Cells were held at a holding potential of –80 mV and pulsed to depolarizing voltage (+30 mV) for variable durations from 50 to 4800 ms in 250 ms increments. was recorded upon repolarization to –50 mV. (c) A plot of relative tail current with 2 μM vandetanib versus the depolarizing duration. The time-dependent decay in relative tail current was fitted by a single exponential function. (d) Voltage clamp pulse protocol and representative recordings of hERG current before and after exposure of the cell to 2 μM vandetanib. (e) Drug-sensitive current expressed as a proportion of the current in the absence and the presence of 2 μM vandetanib. Data are represented by the . Compared with control, and .

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