Radially expanding transglial calcium waves in the intact cerebellum

Department of Molecular Biology and Princeton Neuroscience Institute, Princeton University, Lewis Thomas Laboratory, Washington Road, Princeton, NJ 08544, USA.
Proceedings of the National Academy of Sciences (Impact Factor: 9.81). 03/2009; 106(9):3496-501. DOI: 10.1073/pnas.0809269106
Source: PubMed

ABSTRACT Multicellular glial calcium waves may locally regulate neural activity or brain energetics. Here, we report a diffusion-driven astrocytic signal in the normal, intact brain that spans many astrocytic processes in a confined volume without fully encompassing any one cell. By using 2-photon microscopy in rodent cerebellar cortex labeled with fluorescent indicator dyes or the calcium-sensor protein G-CaMP2, we discovered spontaneous calcium waves that filled approximately ellipsoidal domains of Bergmann glia processes. Waves spread in 3 dimensions at a speed of 4-11 microm/s to a diameter of approximately 50 microm, slowed during expansion, and were reversibly blocked by P2 receptor antagonists. Consistent with the hypothesis that ATP acts as a diffusible trigger of calcium release waves, local ejection of ATP triggered P2 receptor-mediated waves that were refractory to repeated activation. Transglial waves represent a means for purinergic signals to act with local specificity to modulate activity or energetics in local neural circuits.

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