title: Ability of rat microglia to uptake extracellular glutamate.
abstract: Since it has been suggested that microglia in vivo act as glutamate scavengers, this possibility was investigated in primary cultured microglia. The microglia showed specific abilities to uptake (14)C-glutamate depending on incubation time and numbers of cells used. The activity was suppressed by a specific inhibitor for a glial cell-type transporter, glutamate transporter-1 (GLT-1) (EAAT2). However, that of cultured astrocytes was not affected. These results suggest that microglia uptake glutamate by means of GLT-1. Supporting these results, immunoblotting revealed the presence of GLT-1 in the microglia, while only glutamate-aspartate transporter (GLAST) (EAAT1: another glial cell-type transporter) was detected in the astrocytes. All together, these results indicate that microglia can act as glutamate scavengers in vivo by expressing the glutamate transporter GLT-1.
authors: Institute of Life Science, Soka University, 1-236 Tangi-machi, Hachioji, 192-8577, Tokyo, Japan. nakajima@t.soka.ac.jp
authors: K
authors: K
authors: Nakajima
authors: Y
authors: Y
authors: Tohyama
authors: S
authors: S
authors: Kohsaka
authors: T
authors: T
authors: Kurihara
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000819:agonists / Q000037:antagonists & inhibitors / Q000378:metabolism*; D027322:Amino Acid Transport System X-AG; D000818:Animals; D000831:Animals, Newborn; D001253:Astrocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D002250:Carbon Radioisotopes / Q000493:pharmacokinetics; D002478:Cells, Cultured / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D002490:Central Nervous System / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005110:Extracellular Space / Q000187:drug effects* / Q000378:metabolism; D018698:Glutamic Acid / Q000378:metabolism* / Q000493:pharmacokinetics; D017628:Microglia / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D009474:Neurons / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D051381:Rats
chemical_list: D018528:ATP-Binding Cassette Transporters; D027322:Amino Acid Transport System X-AG; D002250:Carbon Radioisotopes; D004791:Enzyme Inhibitors; D018698:Glutamic Acid