TY - JOUR
T1 - Expression of NR1 and NR2A/B subunits of the NMDA receptor in cortical astrocytes
AU - Conti, Fiohenzo
AU - DeBiasi, Silvia
AU - Minelli, Rea
AU - Melone, Marcello
PY - 1996/7
Y1 - 1996/7
N2 - Ionotropic glutamate (Glu) receptors of the N-methyl-D- aspartate type (NMDA) play a fundamental role in many cortical functions. Native NMDA receptors are composed of a heteromeric assembly of different subunits belonging to two classes: NMDAR1 (NR1) and NMDAR2 (NR2). To date, NMDA receptors are believed to be expressed only in neurons, although electrophysiological and in situ hybridization studies have suggested that this class of Glu receptors might be also expressed by some astrocytes. In this study, we have investigated in the cerebral cortex of adult rats the presence of astrocytes expressing NR1 and NR2A/B subunits by immunocytochemistry with specific antibodies, and we show that some distal astrocytic processes, but only rarely astrocytic cell bodies, contain immunoreaction product indicative of NR1 and NR2A/B expression. These findings suggest that at least part of the role NMDA has in cortical functions might depend on the activation of astrocytic NMDA receptors; the subcellular localization of NR1 and NR2A/B subunits in distal processes suggests that NMDA receptors contribute to monitoring Glu levels in the extracellular space.
AB - Ionotropic glutamate (Glu) receptors of the N-methyl-D- aspartate type (NMDA) play a fundamental role in many cortical functions. Native NMDA receptors are composed of a heteromeric assembly of different subunits belonging to two classes: NMDAR1 (NR1) and NMDAR2 (NR2). To date, NMDA receptors are believed to be expressed only in neurons, although electrophysiological and in situ hybridization studies have suggested that this class of Glu receptors might be also expressed by some astrocytes. In this study, we have investigated in the cerebral cortex of adult rats the presence of astrocytes expressing NR1 and NR2A/B subunits by immunocytochemistry with specific antibodies, and we show that some distal astrocytic processes, but only rarely astrocytic cell bodies, contain immunoreaction product indicative of NR1 and NR2A/B expression. These findings suggest that at least part of the role NMDA has in cortical functions might depend on the activation of astrocytic NMDA receptors; the subcellular localization of NR1 and NR2A/B subunits in distal processes suggests that NMDA receptors contribute to monitoring Glu levels in the extracellular space.
KW - Glutamate
KW - ionotropic receptors
KW - neuron-astrocyte communication
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U2 - 10.1002/(SICI)1098-1136(199607)17:3<254::AID-GLIA7>3.0.CO;2-0
DO - 10.1002/(SICI)1098-1136(199607)17:3<254::AID-GLIA7>3.0.CO;2-0
M3 - Article
C2 - 8840166
AN - SCOPUS:0030198387
VL - 17
SP - 254
EP - 258
JO - GLIA
JF - GLIA
SN - 0894-1491
IS - 3
ER -