Enhanced Release Probability without Changes in Synaptic Delay during Analogue-Digital Facilitation
Sami Boudkkazi1,2, Dominique Debanne2
1Physiology Institute, University of Freiburg, 79104 Freiburg, Germany.
Cells
|April 12, 2024
Summary
Synaptic delay remains unchanged during depolarization-induced analogue-digital facilitation (d-ADF) despite increased presynaptic release probability. This indicates compensatory mechanisms involving action potential changes maintain precise neuronal timing.
Area of Science:
- Neuroscience
- Synaptic Plasticity
- Computational Neuroscience
Background:
- Neuronal timing is crucial for brain functions like perception and memory.
- Synaptic delay is influenced by presynaptic release probability and action potential waveform.
- Existing research links synaptic delay changes to various forms of synaptic plasticity.
Purpose of the Study:
- To investigate whether synaptic delay is modulated during depolarization-induced analogue-digital facilitation (d-ADF).
- To understand the interplay between release probability and action potential dynamics in synaptic delay during d-ADF.
Main Methods:
- Electrophysiological recordings from pyramidal L5-L5 cell synapses.
- Induction of d-ADF through prolonged presynaptic depolarization.
- Analysis of synaptic delay, release probability, and action potential properties.
Main Results:
- Depolarization-induced analogue-digital facilitation (d-ADF) elevated presynaptic release probability (Pr).
- Despite elevated Pr, synaptic delay at L5-L5 cell synapses remained unchanged during d-ADF.
- Voltage-inactivation of presynaptic Kv1 channels mediated d-ADF.
Conclusions:
- Synaptic timing is unaffected during d-ADF due to compensatory interactions.
- Presynaptic release probability and action potential-dependent modulations of synaptic delay balance each other.
- Unlike other plasticity forms, d-ADF preserves synaptic timing precision.
Keywords:
context-dependent facilitationlocal circuitsneocortexneuronal timingsynaptic latencysynaptic transmissionMore Related Videos
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