Cell type specificity of neurovascular coupling in cerebral cortex
- Faculty of Mechanical Engineering, Brno University of Technology and Institute of Physical Engineering, Czech Republic
- University of California, San Diego, United States
- Harvard Medical School, United States
- Norwegian University of Life Sciences, Norway
- Oslo University Hospital, Norway
- University of Oslo, Norway
Abstract
Identification of the cellular players and molecular messengers that communicate neuronal activity to the vasculature driving cerebral hemodynamics is important for (1) the basic understanding of cerebrovascular regulation and (2) interpretation of functional Magnetic Resonance Imaging (fMRI) signals. Using a combination of optogenetic stimulation and 2-photon imaging in mice, we demonstrate that selective activation of cortical excitation and inhibition elicits distinct vascular responses and identify the vasoconstrictive mechanism as Neuropeptide Y (NPY) acting on Y1 receptors. The latter implies that task-related negative Blood Oxygenation Level Dependent (BOLD) fMRI signals in the cerebral cortex under normal physiological conditions may be mainly driven by the NPY-positive inhibitory neurons. Further, the NPY-Y1 pathway may offer a potential therapeutic target in cerebrovascular disease.
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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 of the animals were handled according to approved institutional animal care and use committee (IACUC) protocols (#S07360, S14275) of the University of California San Diego.
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© 2016, Uhlirova 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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Cell type specificity of neurovascular coupling in cerebral cortex
eLife 5:e14315.
https://doi.org/10.7554/eLife.14315
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