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Astrocytes pp 499-514 | Cite as

Assessment of Glial Function in the In Vivo Retina

  • Anja I. Srienc
  • Tess E. Kornfield
  • Anusha Mishra
  • Michael A. Burian
  • Eric A. NewmanEmail author
Protocol
Part of the Methods in Molecular Biology book series (MIMB, volume 814)

Abstract

Glial cells, traditionally viewed as passive elements in the CNS, are now known to have many essential functions. Many of these functions have been revealed by work on retinal glial cells. This work has been conducted almost exclusively on ex vivo preparations and it is essential that retinal glial cell functions be characterized in vivo as well. To this end, we describe an in vivo rat preparation to assess the functions of retinal glial cells. The retina of anesthetized, paralyzed rats is viewed with confocal microscopy and laser speckle flowmetry to monitor glial cell responses and retinal blood flow. Retinal glial cells are labeled with the Ca2+ indicator dye Oregon Green 488 BAPTA-1 and the caged Ca2+ compound NP-EGTA by injection of the compounds into the vitreous humor. Glial cells are stimulated by photolysis of caged Ca2+ and the activation state of the cells assessed by monitoring Ca2+ indicator dye fluorescence. We find that, as in the ex vivo retina, retinal glial cells in vivo generate both spontaneous and evoked intercellular Ca2+ waves. We also find that stimulation of glial cells leads to the dilation of neighboring retinal arterioles, supporting the hypothesis that glial cells regulate blood flow in the retina. This in vivo preparation holds great promise for assessing glial cell function in the healthy and pathological retina.

Key words

Glial cell Müller cell Astrocyte Retina In vivo preparation Intracellular calcium Calcium wave Blood flow Confocal microscopy Laser speckle flowmetry 

Notes

Acknowledgments

The development of the in vivo preparation was supported by Fondation Leducq, NIH EY004077, and NIH TRINOD Training Grant.

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Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  • Anja I. Srienc
    • 1
  • Tess E. Kornfield
    • 1
  • Anusha Mishra
    • 1
  • Michael A. Burian
    • 1
  • Eric A. Newman
    • 1
    Email author
  1. 1.Department of NeuroscienceUniversity of MinnesotaMinneapolisUSA

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