ArticleThe Journal of neuroscience : the official journal of the Society for Neuroscience1998
Extrasynaptic glutamate diffusion in the hippocampus: ultrastructural constraints, uptake, and receptor activation.
Article in The Journal of neuroscience : the official journal of the Society for Neuroscience, 1998. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 204 papers.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Who cites it
204 citing papers in PubMed, 448 citations in OpenAlex.
- Article
- An unsuspected physiological role for mGluRIII glutamate receptors in hippocampal area CA1.Cell reports · 2026Article
- Local Chemical Gradients in a Mammalian Cortex Measured In Vivo With a Silicon Nanodialysis Mass Spectrometry Platform.Angewandte Chemie (International ed. in English) · 2026Article
- A biophysically grounded model of glutamatergic synaptic transmission integrating glutamate transport, receptor kinetics, and electrotonic effects.Journal of computational neuroscience · 2026Article
- Extracellular space diffusion modelling identifies distinct functional advantages of glutamatergic and GABAergic synapse geometries.Fluids and barriers of the CNS · 2026Article
- Serotonergic Signaling Rewired: A Lipid Raft-Controlled Model of Synaptic Transmission Grounded in the Fundamental Parameters of Biological Systems.Life (Basel, Switzerland) · 2026Article
- High-Pressure Freezing EM Tomography of Entire Ribbon Synapses in the Retina.The Journal of neuroscience : the official journal of the Society for Neuroscience · 2025Article
- Calcium dynamics in small spaces: Lessons learned from modeling in dendritic spines.Biophysical journal · 2025Review
- Extracellular space diffusion modelling identifies distinct functional advantages of archetypical glutamatergic and GABAergic synapse geometries.bioRxiv : the preprint server for biology · 2025Article
- Aberrant neuronal firing: a paracrine route to glioblastoma expansion.Cell communication and signaling : CCS · 2025Article
- Synaptic cleft geometry modulates NMDAR opening probability by tuning neurotransmitter residence time.Biophysical journal · 2025Article
- Article
- Cortico-striatal action control inherent of opponent cognitive-motivational styles.bioRxiv : the preprint server for biology · 2024Article
- NMDA Receptors: Distribution, Role, and Insights into Neuropsychiatric Disorders.Pharmaceuticals (Basel, Switzerland) · 2024Review
- Celebrating the Birthday of AMPA Receptor Nanodomains: Illuminating the Nanoscale Organization of Excitatory Synapses with 10 Nanocandles.The Journal of neuroscience : the official journal of the Society for Neuroscience · 2024Review
- Ultrastructural differences impact cilia shape and external exposure across cell classes in the visual cortex.Current biology : CB · 2024Article
- The role of extracellular glutamate homeostasis dysregulated by astrocyte in epileptic discharges: a model evidence.Cognitive neurodynamics · 2024Article
- Article
- Afferent convergence to a shared population of interneuron AMPA receptors.Nature communications · 2023Article
- Information Encoding in Bursting Spiking Neural Network Modulated by Astrocytes.Entropy (Basel, Switzerland) · 2023Article
144 more citing papers are in PubMed but not listed here.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
2 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Fast excitatory synapses are generally thought to act as private communication channels between presynaptic and postsynaptic neurons. Some recent findings, however, suggest that glutamate may diffuse out of the synaptic cleft and bind to several subtypes of receptors, either in the perisynaptic membrane or at neighboring synapses. It is not known whether activation of these receptors can occur in response to the release of a single vesicle of glutamate. Here we estimate the spatiotemporal profile of glutamate in the extrasynaptic space after vesicle exocytosis, guided by detailed ultrastructural measurements of the CA1 neuropil in the adult rat. We argue that the vicinity of the synapse can be treated as an isotropic porous medium, in which diffusion is determined by the extracellular volume fraction and the tortuosity factor, and develop novel stereological methods to estimate these parameters. We also estimate the spatial separation between synapses, to ask whether glutamate released at one synapse can activate NMDA and other high-affinity receptors at a neighboring synapse. Kinetic simulations of extrasynaptic glutamate uptake show that transporters rapidly reduce the free concentration of transmitter. Exocytosis of a single vesicle is, however, sufficient to bind to high-affinity receptors situated in the immediate perisynaptic space. The distance separating a typical synapse from its nearest neighbor is approximately 465 nm. Whether glutamate can reach a sufficient concentration to activate NMDA receptors at this distance depends critically on the diffusion coefficient in the extracellular space. If diffusion is much slower than in free aqueous solution, NMDA receptors could mediate crosstalk between neighboring synapses.
Indexed as
Identifiers
9547224PMC6792642W1897919376What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.