Robust but delayed thalamocortical activation of dendritic-targeting inhibitory interneurons

Tan, Z., Hu, H., Huang, Z. J., Agmon, A. (2008) Robust but delayed thalamocortical activation of dendritic-targeting inhibitory interneurons. Proc Natl Acad Sci U S A, 105 (6). pp. 2187-2192.

[img]
Preview
PDF (Paper)
Robust but delayed thalamocortical activation.pdf - Published Version

Download (691Kb) | Preview
URL: https://www.ncbi.nlm.nih.gov/pubmed/18245383
DOI: 10.1073/pnas.0710628105

Abstract

GABA-releasing cortical interneurons are crucial for the neural transformations underlying sensory perception, providing "feedforward" inhibition that constrains the temporal window for synaptic integration. To mediate feedforward inhibition, inhibitory interneurons need to fire in response to ascending thalamocortical inputs, and most previous studies concluded that ascending inputs activate mainly or solely proximally targeting, parvalbumin-containing "fast-spiking" interneurons. However, when thalamocortical axons fire at frequencies that are likely to occur during natural exploratory behavior, activation of fast-spiking interneurons is rapidly and strongly depressed, implying the paradoxical conclusion that feedforward inhibition is absent when it is most needed. To address this issue, we took advantage of lines of transgenic mice in which either parvalbumin- or somatostatin-containing interneurons express GFP and recorded the responses of interneurons from both subtypes to thalamocortical stimulation in vitro. We report that during thalamocortical activation at behaviorally expected frequencies, fast-spiking interneurons were indeed activated only transiently because of rapid depression of their thalamocortical inputs, but a subset of layer 5 somatostatin-containing interneurons were robustly and persistently activated after a delay, due to the facilitation and temporal summation of their thalamocortical excitatory postsynaptic potentials. Somatostatin-containing interneurons are considered distally targeting. Thus, they are likely to provide delayed dendritic inhibition during exploratory behavior, contributing to the maintenance of a balance between cortical excitation and inhibition while leaving a wide temporal window open for synaptic integration and plasticity in distal dendrites.

Item Type: Paper
Subjects: bioinformatics > genomics and proteomics > small molecules > GABAergic
organs, tissues, organelles, cell types and functions > cell types and functions > cell types > dendritic cells
organs, tissues, organelles, cell types and functions > cell types and functions > cell types > dendritic cells
organs, tissues, organelles, cell types and functions > cell types and functions > cell types > dendritic cells

organism description > animal > mammal > rodent > mouse
organs, tissues, organelles, cell types and functions > cell types and functions > cell functions > neural plasticity
neurobiology
organs, tissues, organelles, cell types and functions > cell types and functions > cell types > neurons
organs, tissues, organelles, cell types and functions > cell types and functions > cell types > neurons
organs, tissues, organelles, cell types and functions > cell types and functions > cell types > neurons
CSHL Authors:
Communities: CSHL labs > Huang lab
Depositing User: CSHL Librarian
Date Deposited: 10 Apr 2012 16:30
Last Modified: 10 Jan 2017 15:50
PMCID: PMC2538896
Related URLs:
URI: http://repository.cshl.edu/id/eprint/25813

Actions (login required)

Administrator's edit/view item Administrator's edit/view item
CSHL HomeAbout CSHLResearchEducationNews & FeaturesCampus & Public EventsCareersGiving