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Updated: Mar 29, 2026

Analysis of Astrocyte Territory Volume and Tiling in Thick Free-Floating Tissue Sections
Published on: April 20, 2022
Distinct functional states of astrocytes during sleep and wakefulness: Is norepinephrine the master regulator?
John O'Donnell1, Fengfei Ding1, Maiken Nedergaard1
1Center for Translational Neuromedicine, University of Rochester Medical School, Rochester, NY 14642, USA.
Abstract:
Astrocytes are the chief supportive cells in the central nervous system, but work over the past 20 years have documented that astrocytes also contribute to complex neural processes, such as working memory. Recent discoveries of norepinephrine-mediated astrocytic Ca2+ responses have raised the possibility that astrocytic activity in the adult brain is driven by global responses to changes in behavioral state. Moreover, analysis of the interstitial space volume suggests that astrocytes may undergo changes in cell volume in response to activation of norepinephrine receptors. This review will focus on what is known about astrocytic functions within the nervous system, and how these functions interrelate with rapid changes in behavioral state mediated by norepinephrine signaling.
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