期刊
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
卷 111, 期 25, 页码 9277-9282出版社
NATL ACAD SCIENCES
DOI: 10.1073/pnas.1408525111
关键词
barrel cortex; layer 4 stellate cells; thalamo-cortical transmission; two-photon imaging
资金
- Friedrich-Schiedel-Foundation
- Deutsche Forschungs-gemeinschaft (International Research Training Group) [1373]
- European Commission under the 7th Framework Programme (Project Corticonic)
- European Research Council Advanced Grant
- Deutsche Forschungs-gemeinschaft [SFB870]
Sensory information reaches the cortex through synchronously active thalamic axons, which provide a strong drive to layer 4 (L4) cortical neurons. Because of technical limitations, the dendritic signaling processes underlying the rapid and efficient activation of L4 neurons in vivo remained unknown. Here we introduce an approach that allows the direct monitoring of single dendritic spine Ca2+ signals in L4 spiny stellate cells of the vibrissal mouse cortex in vivo. Our results demonstrate that activation of N-methylD- aspartate (NMDA) receptors is required for sensory-evoked action potential (AP) generation in these neurons. By analyzing NMDA receptor- mediated Ca2+ signaling, we identify whisker stimulationevoked large responses in a subset of dendritic spines. These sensory- stimulation-activated spines, representing predominantly thalamo-cortical input sites, were denser at proximal dendritic regions. The amplitude of sensory- evoked spine Ca2+ signals was independent of the activity of neighboring spines, without evidence for cooperativity. Furthermore, we found that spine Ca2+ signals evoked by back-propagating APs sum linearly with sensory- evoked synaptic Ca2+ signals. Thus, our results identify in sensory information-receiving L4 cortical neurons a linear mode of dendritic integration that underlies the rapid and reliable transfer of peripheral signals to the cortical network.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据