Inhibition of T-type voltage-gated calcium channels by a new scorpion toxin

Nat Neurosci. 1998 Dec;1(8):668-74. doi: 10.1038/3669.


The biophysical properties of T-type voltage-gated calcium channels are well suited to pacemaking and to supporting calcium flux near the resting membrane potential in both excitable and non-excitable cells. We have identified a new scorpion toxin (kurtoxin) that binds to the alpha 1G T-type calcium channel with high affinity and inhibits the channel by modifying voltage-dependent gating. This toxin distinguishes between alpha 1G T-type calcium channels and other types of voltage-gated calcium channels, including alpha 1A, alpha 1B, alpha 1C and alpha 1E. Like the other alpha-scorpion toxins to which it is related, kurtoxin also interacts with voltage-gated sodium channels and slows their inactivation. Kurtoxin will facilitate characterization of the subunit composition of T-type calcium channels and help determine their involvement in electrical and biochemical signaling.

MeSH terms

  • Animals
  • Binding, Competitive / physiology
  • Calcium Channels / drug effects*
  • Calcium Channels / metabolism
  • Calcium Channels, T-Type
  • Electrophysiology
  • Female
  • Ion Channel Gating / drug effects
  • Ion Channel Gating / physiology*
  • Neurotoxins / metabolism
  • Neurotoxins / pharmacology*
  • Oocytes / metabolism
  • Scorpion Venoms / metabolism
  • Scorpion Venoms / pharmacology*
  • Sodium Channels / drug effects
  • Sodium Channels / metabolism
  • Xenopus laevis


  • Calcium Channels
  • Calcium Channels, T-Type
  • Neurotoxins
  • Scorpion Venoms
  • Sodium Channels
  • kurtoxin