Differential effect of homocysteic acid and cysteic acid on changes of inositol phosphates and [Ca2+]i in rat cerebellar granule cells

Won-Ki Kim, Y. S. Pae

Research output: Contribution to journalArticle

Abstract

The present study was undertaken to characterize homocysteic acid (HCA)- and cysteic acid (CA)-mediated formation of inositol phosphates (InsP) in primary culture of rat cerebellar granule cells. HCA and CA stimulated InsP formation in a dose-dependent manner, which was prevented by the N-methyl-D- aspartate (NMDA) receptor antagonist D,L-2-amino-5-phosphopentanoic acid (APV). CA-, but not HCA-, mediated InsP formation was in part prevented by the metabotropic glutamate receptor antagonist α-methyl-4- carboxyphenylglycine ((±)-MCPG). Both HCA- and CA-mediated increases in intracellular calcium concentration were completely blocked by APV, but were not altered by (±)-MCPG. CA-mediated InsP formation was in part prevented by removal of endogenous glutamate. In contrast, the glutamate transport blocker L-aspartic acid-β-hydroxamate synergistically increased CA responses. These data indicate that in cerebellar granule cells HCA mediates InsP formation wholly by activating NMDA receptor. In contrast, CA stimulates InsP formation by activating both NMDA receptor and metabotropic glutamate receptor, and in part by releasing endogenous glutamate into extracellular milieu.

Original languageEnglish
Pages (from-to)41-48
Number of pages8
JournalKorean Journal of Physiology and Pharmacology
Volume2
Issue number1
Publication statusPublished - 1998 Jan 1
Externally publishedYes

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Keywords

  • [Ca]i
  • Cerebellar granule cell
  • Cysteic acid
  • Homocysteic acid
  • Inositol phosphates
  • Metabotropic glutamate (mGlu) receptor
  • N-methyl-D-aspartate (NMDA) receptor
  • Primary culture

ASJC Scopus subject areas

  • Physiology
  • Pharmacology

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