title: Ontogenetic changes in glial fibrillary acid protein phosphorylation, glutamate uptake and glutamine synthetase activity in olfactory bulb of rats.
abstract: Phosphorylation of the glial fibrillary acidic protein (GFAP) in hippocampal and cerebellar slices from immature rats is stimulated by glutamate. This effect occurs via a group II metabotropic glutamate receptor in the hippocampus and an NMDA ionotropic receptor in the cerebellum. We investigated the glutamate modulation of GFAP phosphorylation in the olfactory bulb slices of Wistar rats of different ages (post-natal day 15 = P15, post-natal day 21 = P21 and post-natal day 60 = P60). Our results showed that glutamate stimulates GFAP phosphorylation in young animals and this is mediated by NMDA receptors. We also observed a decrease in glutamate uptake at P60 compared to P15, a finding similar to that found in the hippocampus. The activity of glutamine synthetase was elevated after birth, but was found to decrease with development from P21 to P60. Together, these data confirm the importance of glutamatergic transmission in the olfactory bulb, its developmental regulation in this brain structure and extends the concept of glial involvement in glutamatergic neuron-glial communication.
authors.affiliation: Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, UFRGS, 90035-003, Porto Alegre, RS, Brasil.
authors.forename: Cíntia Eickhoff
authors.initials: CE
authors.lastname: Battú
authors.forename: Graça F R S
authors.initials: GF
authors.lastname: Godinho
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: Thomazi
authors.forename: Lúcia M V
authors.initials: LM
authors.lastname: de Almeida
authors.forename: Carlos Alberto
authors.initials: CA
authors.lastname: Gonçalves
authors.forename: Trícia
authors.initials: T
authors.lastname: Kommers
authors.forename: Susana T
authors.initials: ST
authors.lastname: Wofchuk
mesh_terms: D000367:Age Factors; D000818:Animals; D001692:Biological Transport; D005260:Female; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism*; D005974:Glutamate-Ammonia Ligase / Q000378:metabolism*; D018698:Glutamic Acid / Q000378:metabolism*; D008297:Male; D009830:Olfactory Bulb / Q000254:growth & development / Q000378:metabolism; D010766:Phosphorylation; D051381:Rats; D017208:Rats, Wistar
chemical_list: D005904:Glial Fibrillary Acidic Protein; D018698:Glutamic Acid; D005974:Glutamate-Ammonia Ligase