The rapid re-uptake of extracellular glutamate mediated by a family of high-affinity glutamate transporter proteins is essential to continued glutamatergic signaling and neuronal viability, but the contributions of individual transporter subtypes toward cellular physiology are poorly understood. Because the physiology of glutamate transport in the salamander retina has been well described, we h...

Glutamate uptake, mediated by electrogenic glutamate transporters largely localized in astrocytes, is responsible for the clearance of glutamate released during excitatory synaptic transmission. Glutamate uptake also determines the availability of glutamate for extrasynaptic glutamate receptors. The efficiency of glutamate uptake is commonly estimated from the amplitude of transporter current r...

The goal of this study was to explore the effect of glutamate transporter density on spillover activation of AMPA and NMDA receptors at neighboring synapses by diffusion of glutamate in extracellular space following fast excitatory synaptic release at an active synapse. We used MCell, a Monte Carlo simulator of molecular signaling, to study the release of glutamate and diffusion in 3-D geometri...

Abbreviations: AMPA: α-amino-hydroxy-5-methyl-isoxazole4-propionate; ATP: Adenosine Triphosphate; BDNF: Brain-Derived Neurotrophic Factor; CNS: Central Nervous System; EAAT: Excitatory Amino-Acid Transporter; FGF: Fibroblast Growth Factor; GDNF: Glial-Derived Neurotrophic Factor; GLAST: Glutamate Aspartate Transporter; GLT-1: Glutamate Transporter-1; NO: Nitric Oxide; IL3: Interleukin-3; IL-6: ...

Glutamate transporters are expressed throughout the CNS where their major role is to clear released glutamate from presynaptic terminals. Here, we report a novel function of the transporter in rat pinealocytes. This electrogenic transporter conducted inward current in response to L-glutamate and L- or D-aspartate and depolarized the membrane in patch-clamp experiments. Ca2+ imaging demonstrated...

Three glutamate transporters have been identified in rat, including astroglial transporters GLAST and GLT-1 and a neuronal transporter EAAC1. Here we demonstrate that inhibition of the synthesis of each glutamate transporter subtype using chronic antisense oligonucleotide administration, in vitro and in vivo, selectively and specifically reduced the protein expression and function of glutamate ...

L-Glutamic acid is a major excitatory neurotransmitter in the mammalian central nervous system. The termination of the glutamatergic transmission and the clearance of the excessive, neurotoxic concentrations of glutamate is ensured by a high affinity glutamate uptake system. Four homologous types of Na/K-dependent high affinity glutamate transporters, glutamate/aspartate transporter, glutamate ...

Glutamate transport is coupled to the co-transport of 3 Na(+) and 1 H(+) followed by the counter-transport of 1 K(+). In addition, glutamate and Na(+) binding to glutamate transporters generates an uncoupled anion conductance. The human glial glutamate transporter EAAT1 (excitatory amino acid transporter 1) also allows significant passive and active water transport, which suggests that water pe...

PURPOSE A decrease in the ability of Müller cells to remove glutamate from the extracellular space may play a critical role in the disruption of glutamate homeostasis that occurs in the diabetic retina. Because this amino acid is toxic to retinal neurons and is likely to exacerbate oxidative stress, elucidation of the mechanisms by which glutamate levels are elevated in diabetes may help in the...