nNOS-expressing interneurons control basal and behaviorally-evoked arterial dilation in somatosensory cortex of mice
Abstract
Cortical neural activity is coupled to local arterial diameter and blood flow. However, which neurons control the dynamics of cerebral arteries is not well understood. We dissected the cellular mechanisms controlling the basal diameter and evoked dilation in cortical arteries in awake, head-fixed mice. Locomotion drove robust arterial dilation, increases in gamma band power in the local field potential (LFP), and increases calcium signals in pyramidal and neuronal nitric oxide synthase (nNOS)-expressing neurons. Chemogenetic or pharmocological modulation of overall neural activity up or down caused corresponding increases or decreases in basal arterial diameter. Modulation of pyramidal neuron activity alone had little effect on basal or evoked arterial dilation, despite pronounced changes in the LFP. Modulation of the activity of nNOS-expressing neurons drove changes in the basal and evoked arterial diameter without corresponding changes in population neural activity.
Data availability
The Matlab code and data to generate the figures have been uploaded to Dryad. The DOI for download is here:https://doi.org/10.5061/dryad.b8gtht79hPrior to final acceptance, the Matlab code and data to generate the figures is available here:https://datadryad.org/stash/share/c_aYm6WfvBEeWk4W473h_YFFINirRoS_HgIvsWA2ccM
Article and author information
Author details
Funding
National Institute of Neurological Disorders and Stroke (R01NS078168)
- Patrick J Drew
National Institute of Neurological Disorders and Stroke (R01NS101353)
- Patrick J Drew
National Institute of Neurological Disorders and Stroke (F31NS105461)
- Jordan N Norwood
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All procedures were performed in accordance with protocols approved by the Institutional Animal Care and Use Committee (IACUC) of Pennsylvania State University (protocol # 201042827). All surgeries were performed under isoflurane anesthesia and every effort was made to minimize suffering.
Reviewing Editor
- Anusha Mishra, Oregoh Health and Science University, United States
Publication history
- Received: June 29, 2020
- Accepted: October 2, 2020
- Accepted Manuscript published: October 5, 2020 (version 1)
- Version of Record published: October 14, 2020 (version 2)
Copyright
© 2020, Echagarruga et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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