A HERG-like K+ channel in rat F-11 DRG cell line: pharmacological identification and biophysical characterization

J Physiol. 1996 Oct 1;496 ( Pt 1)(Pt 1):13-23. doi: 10.1113/jphysiol.1996.sp021661.


1. The relationships between the K+ inward rectifier current present in neuroblastoma cells (IIR) and the current encoded by the human ether-á-go-go-related gene (HERG), IHERG, and the rapidly activating repolarizing cardiac current IK(r), were investigated in a rat dorsal root ganglion (DRG) x mouse neuroblastoma hybrid cell line (F-11) using pharmacological and biophysical treatments. 2. IIR shared the pharmacological features described for IK(r), including the sensitivity to the antiarrhythmic drugs E4301 and WAY-123,398, whilst responding to Cs+, Ba2+ and La3+ in a similar way to IHERG. 3. The voltage-dependent gating properties of IIR were similar to those of IK(r) and IHERG, although IIR outward currents were negligible in comparison. 4. In high K+ extracellular solutions devoid of divalent cations, IIR deactivation kinetics were removed resulting in long-lasting currents apparently activated in hyperpolarization, with a marked (2.7-fold) increase in conductance, as recorded from the instantaneous linear current-voltage relationship at -120 mV. Re-addition of Ca2+ restored the original closure of the channel whereas re-addition of Mg2+ reduced the peak current. 5. The IIR described here, the heart IK(r) and the IHERG could be successfully predicted by a unique kinetic model where the voltage dependencies of the activation/inactivation gates were properly voltage shifted. On the whole, IIR seems to be the first example of a HERG-type current constitutively expressed and operating in mammalian cells of the neuronal lineage.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anti-Arrhythmia Agents / pharmacology
  • Benzimidazoles / pharmacology
  • Brain Neoplasms / metabolism
  • Cation Transport Proteins*
  • Cations, Divalent / pharmacology
  • DNA-Binding Proteins*
  • ERG1 Potassium Channel
  • Electrophysiology
  • Ether-A-Go-Go Potassium Channels
  • Ganglia, Spinal / cytology
  • Ganglia, Spinal / metabolism
  • Hybrid Cells
  • Ion Channel Gating / drug effects
  • Kinetics
  • Membrane Potentials / physiology
  • Mice
  • Models, Biological
  • Neuroblastoma / metabolism
  • Patch-Clamp Techniques
  • Piperidines / pharmacology
  • Potassium Channels / drug effects
  • Potassium Channels / metabolism*
  • Potassium Channels, Voltage-Gated*
  • Pyridines / pharmacology
  • Rats
  • Sulfanilamides / pharmacology
  • Trans-Activators*


  • Anti-Arrhythmia Agents
  • Benzimidazoles
  • Cation Transport Proteins
  • Cations, Divalent
  • DNA-Binding Proteins
  • ERG1 Potassium Channel
  • Ether-A-Go-Go Potassium Channels
  • KCNH2 protein, human
  • KCNH6 protein, human
  • Piperidines
  • Potassium Channels
  • Potassium Channels, Voltage-Gated
  • Pyridines
  • Sulfanilamides
  • Trans-Activators
  • E 4031
  • WAY 123398