Dataset Information

Dendrite-Specific Amplification of Weak Synaptic Input during Network Activity In Vivo.

ABSTRACT: Excitatory synaptic input reaches the soma of a cortical excitatory pyramidal neuron via anatomically segregated apical and basal dendrites. In vivo, dendritic inputs are integrated during depolarized network activity, but how network activity affects apical and basal inputs is not understood. Using subcellular two-photon stimulation of Channelrhodopsin2-expressing layer 2/3 pyramidal neurons in somatosensory cortex, nucleus-specific thalamic optogenetic stimulation, and paired recordings, we show that slow, depolarized network activity amplifies small-amplitude synaptic inputs targeted to basal dendrites but reduces the amplitude of all inputs from apical dendrites and the cell soma. Intracellular pharmacology and mathematical modeling suggests that the amplification of weak basal inputs is mediated by postsynaptic voltage-gated channels. Thus, network activity dynamically reconfigures the relative somatic contribution of apical and basal inputs and could act to enhance the detectability of weak synaptic inputs.

SUBMITTER: Ferrarese L

PROVIDER: S-EPMC6172694 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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Dendrite-Specific Amplification of Weak Synaptic Input during Network Activity In Vivo.

Ferrarese Leiron L Jouhanneau Jean-Sébastien JS Remme Michiel W H MWH Kremkow Jens J Katona Gergely G Rózsa Balázs B Schreiber Susanne S Poulet James F A JFA

Cell reports 20180901 13

Excitatory synaptic input reaches the soma of a cortical excitatory pyramidal neuron via anatomically segregated apical and basal dendrites. In vivo, dendritic inputs are integrated during depolarized network activity, but how network activity affects apical and basal inputs is not understood. Using subcellular two-photon stimulation of Channelrhodopsin2-expressing layer 2/3 pyramidal neurons in somatosensory cortex, nucleus-specific thalamic optogenetic stimulation, and paired recordings, we sh ...[more]

PMID: 30257207

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Dataset Information

Dendrite-Specific Amplification of Weak Synaptic Input during Network Activity In Vivo.

Publications

Dendrite-Specific Amplification of Weak Synaptic Input during Network Activity In Vivo.

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