Skip to main content
Article thumbnail
Location of Repository

Functional glutamate transport in rodent optic nerve axons and glia

By Amaia M. Arranz, Ali Hussein, James J.P. Alix, Fernando Pérez-Cerdá, Natalie Allcock, Carlos Matute and Robert Fern

Abstract

This is the author’s submitted draft of the paper published as Glia, 2009, 57 (11), pp. 1168-1177. \ud The definitive version is available at www3.interscience.wiley.com, Doi: 10.1002/glia.20703.Recent findings suggest that synaptic-type glutamate signaling operates between axons and their supporting glial cells. Glutamate reuptake will be a necessary component of such a system. Evidence for glutamate-mediated damage of oligodendroglia somata and processes in white matter suggests that glutamate regulation in white matter structures is also of clinical importance. The expression of glutamate transporters was examined in postnatal Day 14-17 (P14-17) mouse and in mature mouse and rat optic nerve using immuno-histochemistry and immuno-electron microscopy. EAAC1 was the major glutamate transporter detected in oligodendroglia cell membranes in both developing and mature optic nerve, while GLT-1 was the most heavily expressed transporter in the membranes of astrocytes. Both EAAC1 and GLAST were also seen in adult astrocytes, but there was little membrane expression of either at P14-17. GLAST, EAAC1, and GLT-1 were expressed in P14-17 axons with marked GLT-1 expression in the axolemma, while in mature axons EAAC1 was abundant at the node of Ranvier. Functional glutamate transport was probed in P14-17 mouse optic nerve revealing Na+-dependent, TBOA-blockable uptake of D-aspartate in astrocytes, axons, and oligodendrocytes. The data show that in addition to oligodendroglia and astrocytes, axons represent a potential source for extracellular glutamate in white matter during ischaemic conditions, and have the capacity for Na+-dependent glutamate uptake. The findings support the possibility of functional synaptic-type glutamate release from central axons, an event that will require axonal glutamate reuptake.National Institutes of Neurological Disorders and Stroke; Grant Number: NS 44875\ud Ministerio de Educación y Ciencia; Grant Number: SAF2004-06949\ud CIBERNED (Ministerio de Salud y Consumo

Topics: axon, glia, glutamate transport
Publisher: Wiley-Blackwell
Year: 2008
DOI identifier: 10.1002/glia.20703
OAI identifier: oai:lra.le.ac.uk:2381/8035
Journal:
Download PDF:
Sorry, we are unable to provide the full text but you may find it at the following location(s):
  • http://onlinelibrary.wiley.com... (external link)
  • http://hdl.handle.net/2381/803... (external link)
  • Suggested articles


    To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.