Block of kainate receptor channels by Ca2+ in isolated spinal trigeminal neurons of rat

Neuron. 1991 May;6(5):777-84. doi: 10.1016/0896-6273(91)90174-x.

Abstract

Compared with N-methyl-D-aspartate-activated channels, the interaction of Ca2+ with kainate-activated or with quisqualate-activated channels is not well understood. We have studied the effect of Ca2+ on kainate-activated currents in isolated trigeminal neurons and found that Ca2+ inhibits kainate responses. This inhibition occurs not because Ca2+ changes the affinity of kainate to its receptor, but because Ca2+ blocks monovalent cation permeation through kainate-activated channels. This Ca2+ block gives rise to the outward rectification of the kainate responses.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Acetylcholine / pharmacology
  • Acetylcholine / physiology
  • Animals
  • Calcium / pharmacology*
  • Cell Separation
  • Dose-Response Relationship, Drug
  • Electrophysiology
  • Ion Channels / drug effects
  • Ion Channels / physiology
  • Kainic Acid / metabolism*
  • Kainic Acid / pharmacology
  • Magnesium / pharmacology
  • N-Methylaspartate / pharmacology
  • N-Methylaspartate / physiology
  • Neurons / drug effects
  • Neurons / physiology
  • Rats
  • Receptors, Kainic Acid
  • Receptors, Neurotransmitter / drug effects*
  • Receptors, Neurotransmitter / metabolism
  • Trigeminal Nerve / cytology*
  • Trigeminal Nerve / drug effects
  • Trigeminal Nerve / physiology

Substances

  • Ion Channels
  • Receptors, Kainic Acid
  • Receptors, Neurotransmitter
  • N-Methylaspartate
  • Magnesium
  • Acetylcholine
  • Kainic Acid
  • Calcium