title: On-line detection of glutamate release from cultured chick retinospheroids.
abstract: A continuous fluorometric assay was adapted to measure the release of endogenous glutamate from cultured chick retinospheroids. The results obtained with this technique are compared with the release of [3H]D-aspartate from monolayer cultures of chick retina cells. It is shown that although excitatory amino acids may be released in a Ca(2+)-dependent manner, most of the neurotransmitter release from cultured retina cells occurs by reversal of the glutamate transporter. The presence of extracellular Ca2+ may actually inhibit glutamate release by the cells present in the retinospheroids, or the [3H]D-aspartate release by cells in monolayers, when veratridine is the depolarizing agent.
authors: Center for Neuroscience of Coimbra, Department of Zoology, University of Coimbra, Portugal. cbduarte@gemini.ci.uc.pt
authors: C B
authors: CB
authors: Duarte
authors: P F
authors: PF
authors: Santos
authors: J
authors: J
authors: Sánchez-Prieto
authors: A P
authors: AP
authors: Carvalho
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000037:antagonists & inhibitors; D027322:Amino Acid Transport System X-AG; D000818:Animals; D001224:Aspartic Acid / Q000378:metabolism / Q000493:pharmacokinetics; D001692:Biological Transport; D002118:Calcium / Q000378:metabolism; D002122:Calcium Chloride / Q000494:pharmacology; D002478:Cells, Cultured; D002642:Chick Embryo; D005470:Fluorometry; D005971:Glutamates / Q000378:metabolism*; D018377:Neurotransmitter Agents / Q000378:metabolism; D011189:Potassium Chloride / Q000494:pharmacology; D012160:Retina / Q000378:metabolism*; D014701:Veratridine / Q000494:pharmacology
chemical_list: D018528:ATP-Binding Cassette Transporters; D027322:Amino Acid Transport System X-AG; D005971:Glutamates; D018377:Neurotransmitter Agents; D001224:Aspartic Acid; D011189:Potassium Chloride; D014701:Veratridine; D002122:Calcium Chloride; D002118:Calcium