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Astrocytes pp 187-202 | Cite as

Imaging of Local and Global Sodium Signals in Astrocytes

  • Niklas J. Gerkau
  • Karl W. Kafitz
  • Christine R. Rose
Protocol
Part of the Methods in Molecular Biology book series (MIMB, volume 1938)

Abstract

The use of fluorescent chemical indicator dyes enables the dynamic and quantitative imaging of intracellular sodium concentrations and activity-related sodium transients in astrocytes.

Here we describe different approaches for the loading of cellular networks or single astrocytes with sodium-sensitive indicators in brain tissue. Fluorescence signals can then be detected and analyzed with conventional camera-based, wide-field imaging or by employing high-resolution multi-photon microscopy. We furthermore explain strategies for the induction of local and global sodium transients in astrocytes. Finally, we illustrate how fluorescence signals derived from such imaging experiments can be converted into absolute changes of sodium concentration in astrocytes based on an in situ calibration procedure.

Key words

Multi-photon microscopy Wide-field microscopy Astrocytes Perivascular endfeet Hippocampus SBFI Sodium green 

Notes

Acknowledgments

The authors wish to thank Simone Durry and Claudia Rodrigo for expert technical support and Joel Nelson for comments on the manuscript. The studies in the authors laboratory this manuscript were supported by grants from the German Research Foundation (DFG) to C.R.R (Special Priority Programme “Glial Heterogeneity” (SPP 1757), Ro 2327/8-1, 2).

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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  • Niklas J. Gerkau
    • 1
  • Karl W. Kafitz
    • 1
  • Christine R. Rose
    • 1
  1. 1.Institute of NeurobiologyHeinrich Heine University DüsseldorfDüsseldorfGermany

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