Differential Expression of α-Amino-3-Hydroxy-5-Methyl-4-Isoxazole-Propionate Glutamate Receptors in the Rat Striatum during Postnatal Development

Abstract

Alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propio- nate (AMPA)-type glutamate receptors (GluR1–4) are one of the most important ionotropic glutamate receptors in the striatum, a key region of the basal ganglia. The present study investigated the trend of developmental expression of AMPA receptor subunits in the striatum of rats in different developmental stages, i.e., at postnatal day 7 (PND7), PND21 and adult. Perfuse-fixed striatal sections were used. The expression of AMPA subunits was studied by immunofluorescence and reverse transcriptase-polymerase chain reaction (RT-PCR). RT-PCR revealed that the levels of expression of the GluR1 and GluR3 mRNAs were the same among the age groups. The level of GluR2 mRNA was highest in PND21 rats and lowest in adult. The highest level of GluR4 mRNA was detected in rats at PND7. Similar trends of GluR1, GluR2 and GluR2/3 immunoreactivity expression were observed using commercially available specific antibodies. In addition, a large proportion of parvalbumin-immunoreactive GABAergic interneurons in the striatum were found to display GluR1 immunoreactivity in PND21 and adult rats. In contrast, most of the choline acetyltransferase-immunoreactive cholinergic interneurons were found to display GluR2 immunoreactivity but less GluR1 and no GluR2/3 immunoreactivity in PND21 and adult rats. The present study suggests that there is a distinct pattern of expression of AMPA-type receptor mRNAs and proteins in the rat striatum at different stages of development.

.BETA.-Phenylethylamine Stimulates Striatal Acetylcholine Release through Activation of the AMPA Glutamatergic Pathway

“…Genetic and histochemical studies have revealed the localization of both NMDA and AMPA receptors on cholinergic neurons in rat striatum. 23,24) The present study demonstrated the stimulatory function of ionotropic glutamatergic receptors on the release of acetylcholine in the striatum. Although NMDA receptor activation clearly stimulates acetylcholine release, 19,20) the effect of AMPA receptor activation has been controversial.…”

Optogenetics enables functional analysis of human embryonic stem cell–derived grafts in a Parkinson's disease model

“…These data suggest that the graft could enhance EPSPs on host MSNs through the activation of D1 receptors, an effect inhibited by light-induced graft silencing. D1-dependent enhancement of AMPA EPSPs has been reported in several studies in cultured neurons 32–34 and in striatal slices 35–40 . In our experimental protocol, in which electrical stimulation in the nearby corpus callosum evokes repetitive dopamine release at 20-s intervals (Supplementary Fig.…”

Genetic Deletion of NR3A Accelerates Glutamatergic Synapse Maturation

“…To test how NR3A loss affects ionotropic receptor subunit expression, we first had to establish the normal developmental expression of selected subunits in our system. We chose to examine expression of NR1, NR2A, NR2B, and GluR1 subunits due to their high expression levels in developing rodent forebrain and their involvement in synaptic plasticity and maturation (mRNA: [23], [24], [25], [26], [27], [28], [29]; protein: [29], [30], [31], [32], [33], [34], [35], [36], [37], [38], [39], [48]). …”