Functional correlation of NMDA receptor epsilon subunits expression with the properties of single-channel and synaptic currents in the developing cerebellum

J Neurosci. 1996 Jul 15;16(14):4376-82. doi: 10.1523/JNEUROSCI.16-14-04376.1996.


NMDA receptor (NMDAR) subunits epsilon 1-epsilon 4 are expressed differentially with respect to brain region and ontogenic period, but their functional roles still are unclear. We have compared an epsilon 1 subunit-ablated mutant mouse with the wild-type to characterize the effect of epsilon subunit expression on NMDAR-mediated single-channel currents and synaptic currents of granule cells in cerebellar slices. Single-channel and Western blot analyses indicated that the epsilon 2 subunit disappeared gradually during the first postnatal month in both wild-type and mutant mice. Concomitantly, the voltage-dependent Mg2+ block of NMDAR-mediated EPSCs (NMDA-EPSCs) was decreased. Throughout the developmental period studied, postnatal day 7-24 (P7-P24), the decay time course of NMDA-EPSCs in epsilon 1 mutant (-/-) mice was slower than in wild-type mice. We suggest that the expression of the epsilon 3 subunit late in development is responsible for a reduction in the sensitivity of NMDA-EPSCs to block by extracellular Mg2+ and that receptors containing the epsilon 1 subunit determine the fast kinetics of the NMDA-EPSCs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Age Distribution
  • Animals
  • Animals, Newborn
  • Cerebellum / physiology*
  • Magnesium / pharmacology
  • Mice
  • Mice, Mutant Strains
  • Patch-Clamp Techniques
  • Presynaptic Terminals / physiology*
  • Receptors, N-Methyl-D-Aspartate / physiology*


  • Receptors, N-Methyl-D-Aspartate
  • Magnesium