Predominant expression of GluR2 among the AMPA receptor subunits in neuronal progenitor cells of the rat hippocampus.
Cells derived from the hippocampus of embryonic day 18 (E18) rats were cultured in B27-supplemented Neurobasal medium without serum. We found the presence of numerous small cells with round or elliptical somata and fine processes in this primary culture. These cells were first detectable on culture day 8 and gradually increased in number that reached the maximum on approximately day 14. They incorporated bromodeoxyuridine (BrdU) and expressed nestin, a marker of stem cells and progenitor cells. Furthermore, nearly a half of these cells also expressed neuron-specific beta tubulin. On the other hand, they did not express O4 and glial fibrillary acid protein (GFAP), markers of oligodendrocytes and astrocytes, respectively. Thus, these small cells are most likely to be neuronal progenitor cells. The whole-cell patch clamp studies revealed that these cells expressed voltage-gated Na+, Ca2+ and K+ channels. With regard to ligand-gated channels, these cells were sensitive to alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA), but not to N-methyl-D-aspartate (NMDA). The current-voltage relationship of the AMPA-induced current was slightly outwardly rectifying, suggesting that the AMPA receptors contained the GluR2 subunit in their oligomeric assemblies. The single-cell reverse transcription (RT)-PCR analysis revealed that GluR2 is predominant over the other AMPA receptor subunits in these cells. Furthermore, GluR2 was expressed mainly in the flip form.
Hagimura
Norikazu
N
Department of Neurophysiology, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi 371-8511, Japan.
Tsuzuki
Keisuke
K
Iino
Masae
M
Takatsuru
Yusuke
Y
Yoshida
Yukari
Y
Kishi
Shoji
S
Ozawa
Seiji
S
D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D002454:Cell Differentiation / Q000502:physiology; D002478:Cells, Cultured; D018690:Excitatory Amino Acid Agonists / Q000494:pharmacology; D006624:Hippocampus / Q000196:embryology* / Q000378:metabolism*; D007381:Intermediate Filament Proteins / Q000378:metabolism; D007473:Ion Channels / Q000187:drug effects / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000378:metabolism; D064231:Nestin; D009474:Neurons / Q000187:drug effects / Q000378:metabolism*; D018408:Patch-Clamp Techniques; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D018091:Receptors, AMPA / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D013234:Stem Cells / Q000187:drug effects / Q000378:metabolism*; D014404:Tubulin / Q000378:metabolism
D015415:Biomarkers; D018690:Excitatory Amino Acid Agonists; D007381:Intermediate Filament Proteins; D007473:Ion Channels; D009419:Nerve Tissue Proteins; C577486:Nes protein, rat; D064231:Nestin; D012333:RNA, Messenger; D018091:Receptors, AMPA; D014404:Tubulin; C104722:glutamate receptor ionotropic, AMPA 2