Extension of glial processes by activation of Ca2+-permeable AMPA receptor channels.
AMPA type-glutamate receptor channels (AMPARs) assembled without the GluR2 (GluR-B) subunit are characterized by high Ca2+ permeability, and are expressed abundantly in cerebellar Bergmann glial cells. Here we show that the morphology of cultured Bergmann glia-like fusiform cells derived from the rat cerebellum was changed by manipulating expression of Ca2+-permeable AMPARs using adenoviral vector-mediated gene transfer. Converting endogenous Ca2+-permeable AMPARs into Ca2+-impermeable channels by viral-mediated transfer of GluR2 gene induced retraction of glial processes. In contrast, overexpression of Ca2+-permeable AMPARs markedly elongated glial processes. The process extension was blocked by 2,3-Dihydroxy-6-nitro-7-sulfamoylbenzo(F)quinoxaline (NBQX), a specific antagonist of AMPAR. These results indicate that glutamate regulates the morphology of glial processes by activating Ca2+-permeable AMPARs.
Department of Neurosurgery, Gunma University School of Medicine, Maebashi, Japan.
S
S
Ishiuchi
K
K
Tsuzuki
N
N
Yamada
H
H
Okado
A
A
Miwa
H
H
Kuromi
H
H
Yokoo
Y
Y
Nakazato
T
T
Sasaki
S
S
Ozawa
D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D002118:Calcium / Q000378:metabolism*; D048429:Cell Size / Q000187:drug effects / Q000502:physiology; D002478:Cells, Cultured; D002531:Cerebellum / Q000166:cytology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D015870:Gene Expression / Q000502:physiology; D018698:Glutamic Acid / Q000494:pharmacology; D009457:Neuroglia / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D011810:Quinoxalines / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D018091:Receptors, AMPA / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*
D018691:Excitatory Amino Acid Antagonists; D011810:Quinoxalines; D018091:Receptors, AMPA; C062865:2,3-dioxo-6-nitro-7-sulfamoylbenzo(f)quinoxaline; D018698:Glutamic Acid; C104722:glutamate receptor ionotropic, AMPA 2; D002118:Calcium