Persistently enhanced ratio of NMDA and non-NMDA components of rat hippocampal EPSC after block of A1 adenosine receptors at increased [Ca2+]o/[Mg2+]o

Neurosci Lett. 1994 Sep 26;179(1-2):132-6. doi: 10.1016/0304-3940(94)90952-0.

Abstract

NMDA and non-NMDA receptor-mediated components of excitatory post-synaptic current (EPSC) were studied by in situ whole-cell voltage-clamp recordings in the CA1 field of rat hippocampus. We found that the amplitudes ratio of the NMDA to the non-NMDA components can be strongly increased by blocking A1 adenosine receptors. The necessary conditions for this effect are both, increased Ca2+ and lowered Mg2+ in the external medium. The so achieved increase in the NMDA/non-NMDA ratio of EPSC components is irreversible and no longer depends on the activity of A1 adenosine receptors.

MeSH terms

  • Animals
  • Calcium / pharmacology*
  • Electrophysiology
  • Hippocampus / drug effects
  • Hippocampus / metabolism*
  • Hippocampus / physiology
  • In Vitro Techniques
  • Ion Channels / drug effects
  • Ion Channels / metabolism
  • Magnesium / pharmacology*
  • N-Methylaspartate / metabolism*
  • N-Methylaspartate / physiology
  • Neurons / drug effects
  • Neurons / physiology
  • Patch-Clamp Techniques
  • Purinergic P1 Receptor Antagonists*
  • Rats
  • Rats, Wistar
  • Receptors, Glutamate / drug effects
  • Receptors, Glutamate / metabolism*
  • Synapses / drug effects
  • Synapses / physiology*
  • Theophylline / analogs & derivatives
  • Theophylline / pharmacology

Substances

  • Ion Channels
  • Purinergic P1 Receptor Antagonists
  • Receptors, Glutamate
  • 8-cyclopentyl-1,3-dimethylxanthine
  • N-Methylaspartate
  • Theophylline
  • Magnesium
  • Calcium