The class III antiarrhythmic agent E-4031 selectively blocks the inactivating inward-rectifying potassium current in rat anterior pituitary tumor cells (GH3/B6 cells)

@article{Weinsberg1997TheCI,
  title={The class III antiarrhythmic agent E-4031 selectively blocks the inactivating inward-rectifying potassium current in rat anterior pituitary tumor cells (GH3/B6 cells)},
  author={Frank Weinsberg and Christiane K. Bauer and J{\"u}rgen R Schwarz},
  journal={Pfl{\"u}gers Archiv},
  year={1997},
  volume={434},
  pages={1-10}
}
Abstract Hyperpolarization-elicited potassium currents in GH3/B6 cells bathed in high-potassium external solution were recorded to assess effects of the class III antiarrhythmic agent E-4031 on the inactivating inward-rectifying potassium current (IK,IR). E-4031 potently blocked IK,IR with an IC50 value of 10 nM. The complete block of IK,IR achieved with concentrations ≥ 1 μM revealed the presence of a non-inactivating outward-rectifying current which contributed to the membrane currents… 
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TLDR
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