Skip to Content

Coronavirus information for Feinberg.

Download the full-sized PDF of Corticospinal-specific HCN expression in mouse motor cortex: Ih-dependent synaptic integration as a candidate microcircuit mechanism involved in motor control
Download the file

Actions

Download Analytics Citations

Export to: EndNote

Collections

This file is not currently in any collections.

Corticospinal-specific HCN expression in mouse motor cortex: Ih-dependent synaptic integration as a candidate microcircuit mechanism involved in motor control Open Access (recommended)

Descriptions

Resource type(s)
Journal Article
Keyword
Neuroscience
Neocortex
Rights
Attribution 3.0 United States

Creator
Suter, Benjamin
Sheets, Patrick L.
Kiritani, Taro
Chan, Savio
Surmeier, Dalton James
Shepherd, Gordon M G
Abstract
Motor cortex is a key brain center involved in motor control in rodents and other mammals, but specific intracortical mechanisms at the microcircuit level are largely unknown. Neuronal expression of hyperpolarization-activated current (I(h)) is cell class specific throughout the nervous system, but in neocortex, where pyramidal neurons are classified in various ways, a systematic pattern of expression has not been identified. We tested whether I(h) is differentially expressed among projection classes of pyramidal neurons in mouse motor cortex. I(h) expression was high in corticospinal neurons and low in corticostriatal and corticocortical neurons, a pattern mirrored by mRNA levels for HCN1 and Trip8b subunits. Optical mapping experiments showed that I(h) attenuated glutamatergic responses evoked across the apical and basal dendritic arbors of corticospinal but not corticostriatal neurons. Due to I(h), corticospinal neurons resonated, with a broad peak at 4 Hz, and were selectively modulated by -adrenergic stimulation. I(h) reduced the summation of short trains of artificial excitatory postsynaptic potentials (EPSPs) injected at the soma, and similar effects were observed for short trains of actual EPSPs evoked from layer 2/3 neurons. I(h) narrowed the coincidence detection window for EPSPs arriving from separate layer 2/3 inputs, indicating that the dampening effect of I(h) extended to spatially disperse inputs. To test the role of corticospinal I(h) in transforming EPSPs into action potentials, we transfected layer 2/3 pyramidal neurons with channelrhodopsin-2 and used rapid photostimulation across multiple sites to synaptically drive spiking activity in postsynaptic neurons. Blocking I(h) increased layer 2/3-driven spiking in corticospinal but not corticostriatal neurons. Our results imply that I(h)-dependent synaptic integration in corticospinal neurons constitutes an intracortical control mechanism, regulating the efficacy with which local activity in motor cortex is transferred to downstream circuits in the spinal cord. We speculate that modulation of I(h) in corticospinal neurons could provide a microcircuit-level mechanism involved in translating action planning into action execution.
Original Bibliographic Citation
Sheets PL, Suter BA, Kiritani T, Chan CS, Surmeier DJ, Shepherd GM. (2011) Corticospinal-specific HCN expression in mouse motor cortex: Ih-dependent synaptic integration as a candidate microcircuit mechanism involved in motor control. J Neurophysiol 106(5):2216-2231.
Related URL
Publisher
American Physiological Society
DigitalHub. Galter Health Sciences Library
Date Created
2011
Original Identifier
(PMID)21795621
Language
English
Subject: MESH
Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels
Motor Cortex
Mice, Inbred C57BL
Excitatory Postsynaptic Potentials
DOI
10.1152/jn.00232.2011
ARK
ark:/c8131/g3qg6f

File Details

File Properties
Mime type: application/pdf
File size: 3958.5 kB