Effectors of D-[3H]aspartate release from rat cerebellum

R. Svarna, A. Georgopoulos, G. Palaiologos

Research output: Contribution to journalArticlepeer-review

5 Scopus citations

Abstract

The effect of aminooxyacetic acid (AOAA), NH4/+, phenylsuccinate (Phs), ketone bodies (KB) and glutamine (Gln), that might interfere with the biosynthesis of neurotransmitter glutamate on the K+-evoked Ca2+-dependent release of D-[3H]aspartate from rat cerebellar slices was studied. Therefore slices were preincubated in a Krebs-Ringer-bicarbonate-glucose (KR) buffer, loaded with D-[3H]aspartate and superfused in the presence of Ca2+ or when Ca2+ was replaced by Mg2+ or in some cases by EGTA. AOAA, NH4/+ and Phs increase the K+-evoked Ca2+-dependent release of radioactivity by 30%, 68% and 188% compared to the control respectively indicating that these agents are inhibitors of the K+-evoked Ca2+-dependent release of glutamate. KB and Gln had no effect on the Ca2+-dependent release of radioactivity. AOAA, NH4/+, Phs and KB but not Gln increase the total release of radioactivity by 43%, 69%, 139%, and 37% respectively. AOAA, NH4/+ and KB but not Phs or Gin increase the Ca2+-independent release (Mg2+ replacing Ca2+) of radioactivity by 71%, 71% and 108% respectively. The present results indicate that in the cerebellum: 1) Neurotransmitter glutamate is mostly synthesized through the phosphate activated glutaminase (PAG) reaction 2) It is further supported that glutamate released in a Ca2+-dependent manner before entering its pool in the cytosol has to move into the mitochondrial matrix.

Original languageEnglish (US)
Pages (from-to)603-608
Number of pages6
JournalNeurochemical Research
Volume21
Issue number5
DOIs
StatePublished - May 1 1996

Keywords

  • D-aspartate
  • Rat cerebellum
  • mitochondrial ketodicarboxylate carrier
  • neurotransmitter glutamate
  • phosphate activated glutaminase
  • superfusion

Fingerprint Dive into the research topics of 'Effectors of D-[<sup>3</sup>H]aspartate release from rat cerebellum'. Together they form a unique fingerprint.

Cite this