Isolation and characterization of a new immortal rat astrocyte with a high expression of NGF mRNA.
We have established a new line of immortalized rat astrocytes through transfection of plasmid pSV3-neo encoding the large T antigen of simian virus 40 into normal astrocytes. One of these immortalized astrocytes (ACT-57) with a flat and polygonal cell shape, exhibited stable growth in a chemically defined medium (modified N-2 medium) as well as in medium containing ordinary serum. ACT-57, retained a detectable level of expression of glial fibrillary acidic protein (GFAP) and its mRNA, and exhibited a stronger expression of nerve growth factor (NGF) mRNA than that of normal rat astrocytes or C6 glioma cells. NGF mRNA was significantly up-regulated by phorbol ester (12-O-tetradecanoylphorbol 13-acetate, TPA) and gamma-amino-n-butyric acid (GABA) but not by hydrocortisone. None of stimulants (TPA, dibutyryl cyclic AMP (db-cAMP), hydrocortisone, L-glutamate, carbacol, GABA, dopamine, or isoproterenol) changed the expression level of either brain-derived neurotrophic factor (BDNF) or neurotrophin-3 (NT-3). There was a discrete difference between ACT-57 and normal astrocytes in the response to GABA and isoproterenol. These findings imply that normal cortical astrocytes possess a functional heterogeneity whereas the clonal astrocyte, ACT-57, does not, indicating that ACT-57 cells may be useful for in vitro studies of neuron-astrocyte interactions involving the induction of neurotrophic factors such as NGF.
Department of Bioregulation Research, Nagoya City University Medical School, Mizuho-ku, 467-8601, Nagoya, Japan.
M
M
Morikawa
K
K
Asai
M
M
Kokubo
K
K
Fujita
K
K
Yoneda
N
N
Yamamoto
Y
Y
Inoue
J
J
Iida
T
T
Kishimoto
T
T
Kato
D000818:Animals; D001253:Astrocytes / Q000166:cytology* / Q000378:metabolism*; D001921:Brain / Q000166:cytology / Q000378:metabolism; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics; D018929:Cell Culture Techniques / Q000379:methods; D002478:Cells, Cultured; D004622:Embryo, Mammalian; D007621:Karyotyping; D020932:Nerve Growth Factor / Q000235:genetics*; D020933:Neurotrophin 3 / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014158:Transcription, Genetic
D019208:Brain-Derived Neurotrophic Factor; D020933:Neurotrophin 3; D012333:RNA, Messenger; D020932:Nerve Growth Factor