Activation of extrasynaptic NMDARs at individual parallel fiber-molecular layer interneuron synapses in cerebellum

Ben Nahir, Craig Jahr

Research output: Contribution to journalArticle

18 Citations (Scopus)

Abstract

NMDA receptors (NMDARs) expressed by cerebellar molecular layer interneurons (MLIs) are not activated by single exocytotic events but can respond to glutamate spillover following coactivation of adjacent parallel fibers (PFs), indicating that NMDARs are perisynaptic. Several types of synaptic plasticity rely on these receptors but whether they are activated at isolated synapses is not known. Using a combination of electrophysiological and optical recording techniques in acute slices of rat cerebellum, along with modeling, we find that repetitive activation of single PF-MLI synapses can activate NMDARs in MLIs. High-frequency stimulation, multivesicular release (MVR), or asynchronous release can each activate NMDARs. Frequency facilitation was found at all PF-MLI synapses but, while some showed robust MVR with increased release probability, most were limited to univesicular release. Together, these results reveal a functional diversity of PF synapses, which use different mechanisms to activate NMDARs.

Original languageEnglish (US)
Pages (from-to)16323-16333
Number of pages11
JournalJournal of Neuroscience
Volume33
Issue number41
DOIs
StatePublished - 2013

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Interneurons
N-Methyl-D-Aspartate Receptors
Synapses
Cerebellum
Neuronal Plasticity
Glutamic Acid

ASJC Scopus subject areas

  • Neuroscience(all)
  • Medicine(all)

Cite this

Activation of extrasynaptic NMDARs at individual parallel fiber-molecular layer interneuron synapses in cerebellum. / Nahir, Ben; Jahr, Craig.

In: Journal of Neuroscience, Vol. 33, No. 41, 2013, p. 16323-16333.

Research output: Contribution to journalArticle

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