From development to disease: Diverse functions of NMDA-type glutamate receptors in the lower auditory pathway

J. T. Sanchez*, S. Ghelani, S. Otto-Meyer

*Corresponding author for this work

Research output: Contribution to journalReview article

18 Scopus citations

Abstract

N-methyl- d-aspartate receptors (NMDA-Rs) are located at each synapse in the lower auditory pathway of mammals and avians. Characterized by a slow and long-lasting excitatory response upon glutamate activation, their existence in a sensory system biologically engineered for speed and precision seems counterintuitive. In this review we consider the diverse functions of NMDA-Rs. Their developmental regulation and unique subunit composition in the inner ear promote protective and neurotrophic roles following acute insult by regulating AMPA-R expression and assisting in the restoration of synaptic inputs. This contrasts with chronic damage where overactivation of NMDA-Rs is implicated in neuronal death. These functions are thought to be involved in auditory diseases, including noise-induced hearing loss, neural presbycusis, and tinnitus via aberrant excitation. A more traditional role emerges in the developing auditory brainstem, where NMDA-Rs are downregulated and switch subunit composition with maturation. Their biophysical properties also contribute to synaptic dynamics resembling long-term plasticity. At mature synapses they support reliable auditory processing by increasing the probability of action potential generation, regulating first-spike latency, and maintaining reliable action potential firing. Thus, NMDA-R functions in the lower auditory pathway are diverse, contributing to synaptic development, plasticity, temporal processing, and diseases.

Original languageEnglish (US)
Pages (from-to)248-259
Number of pages12
JournalNeuroscience
Volume285
DOIs
StatePublished - Jan 9 2015

    Fingerprint

Keywords

  • Auditory development
  • Auditory disease
  • Glutamate
  • Hearing
  • N-methyl-d-aspartate receptors

ASJC Scopus subject areas

  • Neuroscience(all)

Cite this