Physiological evidence that D-aspartate activates a current distinct from ionotropic glutamate receptor currents in Aplysia californica neurons

Stephen L. Carlson, Lynne A. Fieber

Research output: Contribution to journalArticle

10 Scopus citations

Abstract

DAspartate (D-Asp) activates an excitatory current in neurons of Aplysia californica. Although D-Asp is presumed to activate a subset of L-glutamate (L-Glu) channels, the identities of putative D-Asp receptors and channels are unclear. Whole cell voltage- and current-clamp studies using primary cultures of Aplysia buccal S cluster (BSC) neurons were executed to characterize D-Asp-activated ion channels. Both D-Asp and L-Glu evoked currents with similar current-voltage relationships, amplitudes, and relatively slow time courses of activation and inactivation when agonists were pressure applied. D-Aspinduced currents, however, were faster and desensitized longer, requiring 40 s to return to full amplitude. Of cells exposed to both agonists, 25% had D-Asp- but not L-Glu-induced currents, suggesting a receptor for D-Asp that was independent of L-Glu receptors. D-Asp channels were permeable to Na + and K +, but not Ca 2+, and were vulnerable to voltage-dependent Mg 2+ block similarly to vertebrate NMDA receptor (NMDAR) channels. D-Asp may activate both NMDARs and non-L-Glu receptors in the nervous system of Aplysia.

Original languageEnglish (US)
Pages (from-to)1629-1636
Number of pages8
JournalJournal of neurophysiology
Volume106
Issue number4
DOIs
StatePublished - Oct 2011

Keywords

  • Buccal ganglion
  • Cation channel
  • Invertebrate
  • Nmethyl-D-aspartate
  • Reversal potential

ASJC Scopus subject areas

  • Physiology
  • Neuroscience(all)

Fingerprint Dive into the research topics of 'Physiological evidence that D-aspartate activates a current distinct from ionotropic glutamate receptor currents in Aplysia californica neurons'. Together they form a unique fingerprint.

  • Cite this