Presence of N-methyl-D-aspartate (NMDA) receptors in neuroblastoma x glioma hybrid NG108-15 cells-analysis using [45Ca2+]influx and [3H]MK-801 binding as functional measures

Brain Res Mol Brain Res. 1994 Mar;22(1-4):166-72. doi: 10.1016/0169-328x(94)90044-2.


In the present study, we have attempted to clarify whether neuroblastoma glioma hybrid NG 108-15 cells (NG cells) possess the NMDA receptor complex using [45Ca2+]influx and [3H]MK-801 binding as functional measures. Glutamate and NMDA dose-dependently increased [45Ca2+]influx and these increases were further enhanced by glycine. Scatchard analysis revealed the presence of a high-affinity binding site for [3H]MK-801 with a KD of 18.8 nM and a Bmax of 0.328 pmol/mg protein. This [3H]MK-801 binding was also increased by NMDA in a dose-dependent manner and this increase was further enhanced by glycine. Both ketamine and MK-801 inhibited glutamate- and NMDA-induced [45Ca2+]influx as well as the increase of [3H]MK-801 binding in a dose-dependent manner. Similarly, Mg2+ and Zn2+ dose-dependently reduced both glutamate-induced [45Ca2+]influx and [3H]MK-801 binding. Spermine, one of the polyamines, showed a biphasic stimulatory effects on glutamate-induced [45Ca2+]influx and [3H]MK-801 binding. These results indicate that NG cells possess a pharmacologically distinct NMDA receptor complex and suggest that these cells may be useful for the analyses on pharmacological and biochemical characteristics of the NMDA receptor complex.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Calcium Radioisotopes
  • Cations, Divalent / pharmacology
  • Dizocilpine Maleate / metabolism*
  • Glioma / chemistry
  • Glutamates / pharmacology
  • Glutamic Acid
  • Glycine / pharmacology
  • Hybrid Cells / chemistry*
  • N-Methylaspartate / pharmacology
  • Neuroblastoma / chemistry
  • Radioligand Assay
  • Receptors, N-Methyl-D-Aspartate / analysis*
  • Spermine / pharmacology
  • Tritium


  • Calcium Radioisotopes
  • Cations, Divalent
  • Glutamates
  • Receptors, N-Methyl-D-Aspartate
  • Tritium
  • Spermine
  • Glutamic Acid
  • N-Methylaspartate
  • Dizocilpine Maleate
  • Glycine