title: Differential development of vesicular glutamate transporters in brain: an in vitro study of cerebellar granule cells.
abstract: The cerebellar granule cells have been extensively used for studies on metabolism, neurotransmission and neurotoxicology, since they can easily be grown in cultures. However, knowledge about the development of different proteins essential for synaptic transmission in these cells is lacking. This study has characterized the developmental profiles of the vesicular glutamate transporters (VGLUTs) and the synaptic vesicle proteins synapsins and synaptophysin in cerebellar granule cells and in co-cultures containing both granule cells and astrocytes. The protein levels of VGLUT2 decreased by approximately 70% from days 2 to 7 in vitro, whereas the levels of VGLUT1 increased by approximately 95%. Protein levels of synapsin I, synapsin IIIa and synaptophysin showed a developmental pattern similar to VGLUT1 while synapsin II and VGLUT3 were absent. The mRNA expressions of VGLUT1 and VGLUT2 were in accordance with the protein levels. The results indicate both that cerebellar granule cells are mature at approximately 7 days in vitro, and that the up-regulation of VGLUT1 and down-regulation of VGLUT2 in cerebellar granule cells are both independent of surrounding astrocytes and neuronal input. The results of this study are discussed in relation to general developmental profiles of VGLUTs in other brain regions.
authors.affiliation: Department of Biochemistry, Institute of Basic Medical Sciences, University of Oslo, P.O. Box 1112, Blindern, N-0317 Oslo, Norway.
authors.forename: Olof Ehlers
authors.initials: OE
authors.lastname: Hallberg
authors.forename: Inger Lise
authors.initials: IL
authors.lastname: Bogen
authors.forename: Trine
authors.initials: T
authors.lastname: Reistad
authors.forename: Kristin Huse
authors.initials: KH
authors.lastname: Haug
authors.forename: Marianne S
authors.initials: MS
authors.lastname: Wright
authors.forename: Frode
authors.initials: F
authors.lastname: Fonnum
authors.forename: S Ivar
authors.initials: SI
authors.lastname: Walaas
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000166:cytology; D001921:Brain / Q000033:anatomy & histology / Q000378:metabolism; D002531:Cerebellum / Q000166:cytology / Q000254:growth & development / Q000378:metabolism*; D018920:Coculture Techniques; D018507:Gene Expression Regulation, Developmental; D009474:Neurons / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D016704:Synapsins / Q000096:biosynthesis; D016708:Synaptophysin / Q000096:biosynthesis; D050598:Vesicular Glutamate Transport Protein 1 / Q000096:biosynthesis*; D050599:Vesicular Glutamate Transport Protein 2 / Q000096:biosynthesis*; D050496:Vesicular Glutamate Transport Proteins / Q000096:biosynthesis*
chemical_list: C493475:Slc17a6 protein, rat; C493466:Slc17a7 protein, rat; C482103:Slc17a8 protein, rat; D016704:Synapsins; D016708:Synaptophysin; D050598:Vesicular Glutamate Transport Protein 1; D050599:Vesicular Glutamate Transport Protein 2; D050496:Vesicular Glutamate Transport Proteins