Spermine enhanced binding to the glycine site associated with the N-methyl-D-aspartate receptor complex

A. I. Sacaan, K. M. Johnson

Research output: Contribution to journalArticle

75 Scopus citations


Spermine enhanced strychnine-insensitive [3H]glycine binding 3-fold with an EC50 of 27 ± 3.1 μM. Spermidine and putrescine were without effect, whereas the ethylenediamine analog of spermine had an intermediate effect. Eadie-Hofstee analysis revealed that spermine increased the affinity of glycine for its receptors without a significant change in receptor density. This effect persisted in the presence of glycine or N-methyl-D-aspartate receptor antagonists. Furthermore, spermine produced a leftward shift in the IC50 of glycine agonists in displacing [3H]glycine binding, without altering the IC50 for glycine antagonists. These data indicate that spermine interacts with the glycine receptor through a novel binding site and, further, that spermine can be used to discriminate glycine agonist and antagonist binding.

Original languageEnglish (US)
Pages (from-to)836-839
Number of pages4
JournalMolecular pharmacology
Issue number6
StatePublished - Dec 1 1989


ASJC Scopus subject areas

  • Molecular Medicine
  • Pharmacology

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