Selective release of N-acetylaspartylglutamate from rat optic nerve terminals in vivo

G. Tsai, Barbara Slusher, J. J. Vornov, J. K. Deshpande, J. T. Coyle

Research output: Contribution to journalArticle

Abstract

Glutamate (Glu) and aspartate (Asp) are considered to be the neurotransmitters of the optic pathway in submammalian species, but their roles in mammals is uncertain. Recently, N-acetylaspartylglutamate (NAAG) has been proposed as a neurotransmitter in mammalian optic pathway; however, the release of endogenous NAAG on stimulation of the optic pathway has not been demonstrated. Using an in vivo microdialysis technique, we now report that electrical stimulation of rat optic nerve markedly increased the extracellular concentration of NAAG but not Glu/Asp in superficial superior colliculus where retinal afferents terminate, whereas non-specific stimulation of neurotransmitter release by high potassium or veratridine increased both extracellular Glu/Asp and NAAG concentration in the perfusate. The release of NAAG was dependent on Ca2+ and the presence of optic terminals. We conclude that NAAG is a better candidate as a neurotransmitter of rat optic nerve terminals than Glu/Asp.

Original languageEnglish (US)
Pages (from-to)313-316
Number of pages4
JournalBrain Research
Volume518
Issue number1-2
DOIs
StatePublished - Jun 4 1990

Fingerprint

Optic Nerve
Aspartic Acid
Neurotransmitter Agents
Glutamic Acid
Veratridine
Superior Colliculi
Microdialysis
Electric Stimulation
N-acetyl-1-aspartylglutamic acid
Mammals
Potassium

Keywords

  • Aspartate
  • Glutamate
  • In vivo dialysis
  • N-Acetylaspartylglutamate
  • Neurotransmitter
  • Optic pathway
  • Release

ASJC Scopus subject areas

  • Developmental Biology
  • Molecular Biology
  • Clinical Neurology
  • Neuroscience(all)

Cite this

Selective release of N-acetylaspartylglutamate from rat optic nerve terminals in vivo. / Tsai, G.; Slusher, Barbara; Vornov, J. J.; Deshpande, J. K.; Coyle, J. T.

In: Brain Research, Vol. 518, No. 1-2, 04.06.1990, p. 313-316.

Research output: Contribution to journalArticle

Tsai, G. ; Slusher, Barbara ; Vornov, J. J. ; Deshpande, J. K. ; Coyle, J. T. / Selective release of N-acetylaspartylglutamate from rat optic nerve terminals in vivo. In: Brain Research. 1990 ; Vol. 518, No. 1-2. pp. 313-316.
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