Frequency-dependent mobilization of heterogeneous pools of synaptic vesicles shapes presynaptic plasticity

Elife. 2017 Oct 9:6:e28935. doi: 10.7554/eLife.28935.


The segregation of the readily releasable pool of synaptic vesicles (RRP) in sub-pools that are differentially poised for exocytosis shapes short-term plasticity. However, the frequency-dependent mobilization of these sub-pools is poorly understood. Using slice recordings and modeling of synaptic activity at cerebellar granule cell to Purkinje cell synapses of mice, we describe two sub-pools in the RRP that can be differentially recruited upon ultrafast changes in the stimulation frequency. We show that at low-frequency stimulations, a first sub-pool is gradually silenced, leading to full blockage of synaptic transmission. Conversely, a second pool of synaptic vesicles that cannot be released by a single stimulus is recruited within milliseconds by high-frequency stimulation and support an ultrafast recovery of neurotransmitter release after low-frequency depression. This frequency-dependent mobilization or silencing of sub-pools in the RRP in terminals of granule cells may play a role in the filtering of sensorimotor information in the cerebellum.

Keywords: Purkinje cell; cerebellum; mouse; neuroscience; neurotransmitter release; parallel fibers; short-term plasticity; synaptic vesicles.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Action Potentials
  • Animals
  • Cerebellum / physiology*
  • Mice
  • Neuronal Plasticity*
  • Neurons / physiology*
  • Presynaptic Terminals / metabolism*
  • Synaptic Transmission
  • Synaptic Vesicles / metabolism*

Grants and funding

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.