title: Quantal glutamate release is essential for reliable neuronal encodings in cerebral networks.
abstract: BACKGROUND
  The neurons and synapses work coordinately to program the brain codes of controlling cognition and behaviors. Spike patterns at the presynaptic neurons regulate synaptic transmission. The quantitative regulations of synapse dynamics in spike encoding at the postsynaptic neurons remain unclear.
  
  
  RESULTS
  With dual whole-cell recordings at synapse-paired cells in mouse cortical slices, we have investigated the regulation of synapse dynamics to neuronal spike encoding at cerebral circuits assembled by pyramidal neurons and GABAergic ones. Our studies at unitary synapses show that postsynaptic responses are constant over time, such as glutamate receptor-channel currents at GABAergic neurons and glutamate transport currents at astrocytes, indicating quantal glutamate release. In terms of its physiological impact, our results demonstrate that the signals integrated from quantal glutamatergic synapses drive spike encoding at GABAergic neurons reliably, which in turn precisely set spike encoding at pyramidal neurons through feedback inhibition.
  
  
  CONCLUSIONS
  Our studies provide the evidences for the quantal glutamate release to drive the spike encodings precisely in cortical circuits, which may be essential for programming the reliable codes in the brain to manage well-organized behaviors.
authors.affiliation: State Key Lab for Brain and Cognitive Sciences, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.
authors.forename: Jiandong
authors.initials: J
authors.lastname: Yu
authors.forename: Hao
authors.initials: H
authors.lastname: Qian
authors.forename: Na
authors.initials: N
authors.lastname: Chen
authors.forename: Jin-Hui
authors.initials: JH
authors.lastname: Wang
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000166:cytology / Q000378:metabolism*; D002478:Cells, Cultured; D018698:Glutamic Acid / Q000378:metabolism*; D051379:Mice; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D018408:Patch-Clamp Techniques; D055366:Synaptic Potentials / Q000502:physiology*; D009435:Synaptic Transmission / Q000502:physiology*; D005680:gamma-Aminobutyric Acid / Q000378:metabolism*
chemical_list: D018698:Glutamic Acid; D005680:gamma-Aminobutyric Acid