HAL will be down for maintenance from Friday, June 10 at 4pm through Monday, June 13 at 9am. More information
Skip to Main content Skip to Navigation
Journal articles

Presynaptic hyperpolarization induces a fast analogue modulation of spike-evoked transmission mediated by axonal sodium channels

Abstract : In the mammalian brain, synaptic transmission usually depends on presynaptic action potentials (APs) in an all-or-none (or digital) manner. Recent studies suggest, however, that subthreshold depolarization in the presynaptic cell facilitates spike-evoked transmission, thus creating an analogue modulation of a digital process (or analogue–digital (AD) modulation). At most synapses, this process is slow and not ideally suited for the fast dynamics of neural networks. We show here that transmission at CA3–CA3 and L5–L5 synapses can be enhanced by brief presynaptic hyperpolarization such as an inhibitory postsynaptic potential (IPSP). Using dual soma–axon patch recordings and live imaging, we find that this hyperpolarization-induced AD facilitation (h-ADF) is due to the recovery from inactivation of Nav channels controlling AP amplitude in the axon. Incorporated in a network model, h-ADF promotes both pyramidal cell synchrony and gamma oscillations. In conclusion, cortical excitatory synapses in local circuits display hyperpolarization-induced facilitation of spike-evoked synaptic transmission that promotes network synchrony.
Document type :
Journal articles
Complete list of metadata

Cited literature [44 references]  Display  Hide  Download

https://hal-amu.archives-ouvertes.fr/hal-01766831
Contributor : Dominique Debanne Connect in order to contact the contributor
Submitted on : Saturday, April 14, 2018 - 12:37:37 PM
Last modification on : Friday, October 22, 2021 - 3:26:50 AM

File

Rama-Debanne-Nat-Comm-2015.pdf
Publisher files allowed on an open archive

Identifiers

Collections

Citation

Sylvain Rama, Mickael Zbili, Andrzej Bialowas, Laure Fronzaroli-Molinieres, Norbert Ankri, et al.. Presynaptic hyperpolarization induces a fast analogue modulation of spike-evoked transmission mediated by axonal sodium channels. Nature Communications, Nature Publishing Group, 2015, 6 (1), pp.10163. ⟨10.1038/ncomms10163⟩. ⟨hal-01766831⟩

Share

Metrics

Record views

35

Files downloads

63