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Experimental Brain Research

, Volume 81, Issue 1, pp 209–212 | Cite as

Voltage sensitivity of NMDA-receptor mediated postsynaptic currents

  • A. Konnerth
  • B. U. Keller
  • K. Ballanyi
  • Y. Yaari
Research Note

Summary

Patch-clamp techniques were used to record pharmacologically-isolated N-methyl-D-aspartate-mediated excitatory postsynaptic currents (NMDA-EPSCs) from dentate granule cells in thin rat hippocampal slices. Membrane voltage modulated these EPSCs in two ways. Firstly, depolarization from resting potential enhanced EPSC amplitudes, as expected for a voltage-dependent block by Mg2+ of synaptically activated NMDA receptor channels. Secondly, depolarization markedly prolonged the time course of decay of NMDA-EPSCs in normal and low extracellular Mg2+. Both mechanisms were complementary in establishing a strong dependence between membrane potential and the amount of charge, namely Ca2+, transferred through synaptically activated NMDA receptor channels, that presumably underlies induction of long-term potentiation in the hippocampus.

Key words

NMDA Excitatory postsynaptic current Voltage sensitivity Patch clamp Thin hippocampal slice Rat 

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Copyright information

© Springer-Verlag 1990

Authors and Affiliations

  • A. Konnerth
    • 1
  • B. U. Keller
    • 1
  • K. Ballanyi
    • 1
  • Y. Yaari
    • 2
  1. 1.Zelluläre Neurophysiologie, Max-Planck-Institut für biophysikalische ChemieGöttingenFederal Republic of Germany
  2. 2.Department of PhysiologyHebrew University-Hadassah Medical SchoolJerusalemIsrael

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