Mechanism of glutamate-induced [Ca2+]i increase in substantia gelatinosa neurons of juvenile rats

Jung Sung Jun, Jeong Sook Choi, Jiyeon Kwak, Jun Kim, Jong Whan Kim, Sang Jeong Kim

Research output: Contribution to journalArticle

Abstract

The glutamate receptors (GluRs) are key receptors for modulatory synaptic events in the central nervous system. It has been reported that glutamate increases the intracellular Ca2+ concentration ([Ca2+]i) and induces cytotoxicity. In the present study, we investigated whether the glutamate-induced [Ca2+]i increase was associated with the activation of ionotropic (iGluR) and metabotropic GluRs (mGluR) in substantia gelatinosa neurons, using spinal cord slice of juvenile rats (10-21 day). [Ca2+]i was measured using conventional imaging techniques, which was combined with whole-cell patch clamp recording by incorporating fura-2 in the patch pipette. At physiological concentration of extracellular Ca2+, the inward current and [Ca2+]i increase were induced by membrane depolarization and application of glutamate. Dose-response relationship with glutamate was observed in both Ca2+ signal and inward current. The glutamate-induced [Ca2+]i increase at holding potential of -70 mV was blocked by CNQX, an AMPA receptor blocker, but not by AP-5, a NMDA receptor blocker. The glutamate-induced [Ca2+]i increase in Ca2+ free condition was not affected by iGluR blockers. A selective mGluR (group I) agonist, RS-3,5-dihydroxyphenylglycine (DHPG), induced [Ca2+]i increase at holding potential of -70 mV in SG neurons. These findings suggest that the glutamate-induced [Ca2+]i increase is associated with AMPA-sensitive iGluR and group I mGluR in SG neurons of rats.

Original languageEnglish
Pages (from-to)53-57
Number of pages5
JournalKorean Journal of Physiology and Pharmacology
Volume7
Issue number2
StatePublished - 2003 Apr 1

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Substantia Gelatinosa
Glutamic Acid
Neurons
6-Cyano-7-nitroquinoxaline-2,3-dione
Ionotropic Glutamate Receptors
alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid
Metabotropic Glutamate Receptors
Neurotransmitter Receptor
AMPA Receptors
Fura-2
Glutamate Receptors
N-Methyl-D-Aspartate Receptors
Spinal Cord
Central Nervous System
Membranes

Keywords

  • AMPA receptor
  • Glutamate
  • Intracellular Ca concentration
  • Metabotropic glutamate receptor
  • NMDA receptor
  • Substantia gelatinosa neuron

Cite this

Jun, Jung Sung ; Choi, Jeong Sook ; Kwak, Jiyeon ; Kim, Jun ; Kim, Jong Whan ; Kim, Sang Jeong. / Mechanism of glutamate-induced [Ca2+]i increase in substantia gelatinosa neurons of juvenile rats. In: Korean Journal of Physiology and Pharmacology. 2003 ; Vol. 7, No. 2. pp. 53-57.
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Mechanism of glutamate-induced [Ca2+]i increase in substantia gelatinosa neurons of juvenile rats. / Jun, Jung Sung; Choi, Jeong Sook; Kwak, Jiyeon; Kim, Jun; Kim, Jong Whan; Kim, Sang Jeong.

In: Korean Journal of Physiology and Pharmacology, Vol. 7, No. 2, 01.04.2003, p. 53-57.

Research output: Contribution to journalArticle

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T1 - Mechanism of glutamate-induced [Ca2+]i increase in substantia gelatinosa neurons of juvenile rats

AU - Jun, Jung Sung

AU - Choi, Jeong Sook

AU - Kwak, Jiyeon

AU - Kim, Jun

AU - Kim, Jong Whan

AU - Kim, Sang Jeong

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