Astrocyte morphology is confined by cortical functional boundaries in mammals ranging from mice to human
Abstract
Cortical blood flow can be modulated by local activity across a range of species; from barrel-specific blood flow in the rodent somatosensory cortex to the human cortex, where BOLD-fMRI reveals numerous functional borders. However, it appears that the distribution of blood capillaries largely ignores these functional boundaries. Here we report that, by contrast, astrocytes, a major player in blood-flow control, show a striking morphological sensitivity to functional borders. Specifically, we show that astrocyte processes are structurally confined by barrel boundaries in the mouse, by the border of primary auditory cortex in the rat and by layers IIIa/b and Cytochrome Oxidase (CO)-blobs boundaries in the human primary visual cortex. Thus, astrocytes which are critical elements in neuro-hemodynamic coupling show a significant anatomical segregation along functional boundaries across different mammalian species. These results may open a new anatomical marker for delineating functional borders across species, including post-mortem human brains.
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Author details
Ethics
Animal experimentation: All the animal experiments were approved by the Institutional Animal Care and Use Committee of the Weizmann Institute. Protocol number 20640915-2.
Human subjects: Right human brain occipital lobe was provided by the Netherlands Brain Bank
Reviewing Editor
- Doris Y Tsao, California Institute of Technology, United States
Version history
- Received: March 9, 2016
- Accepted: June 9, 2016
- Accepted Manuscript published: June 10, 2016 (version 1)
- Version of Record published: July 14, 2016 (version 2)
Copyright
© 2016, Eilam 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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