Calcium dynamics of cortical astrocytic networks in vivo.
Large and long-lasting cytosolic calcium surges in astrocytes have been described in cultured cells and acute slice preparations. The mechanisms that give rise to these calcium events have been extensively studied in vitro. However, their existence and functions in the intact brain are unknown. We have topically applied Fluo-4 AM on the cerebral cortex of anesthetized rats, and imaged cytosolic calcium fluctuation in astrocyte populations of superficial cortical layers in vivo, using two-photon laser scanning microscopy. Spontaneous [Ca(2+)](i) events in individual astrocytes were similar to those observed in vitro. Coordination of [Ca(2+)](i) events among astrocytes was indicated by the broad cross-correlograms. Increased neuronal discharge was associated with increased astrocytic [Ca(2+)](i) activity in individual cells and a robust coordination of [Ca(2+)](i) signals in neighboring astrocytes. These findings indicate potential neuron-glia communication in the intact brain.
Hirase
Hajime
H
Center for Molecular and Behavioral Neuroscience, Rutgers University, Newark, New Jersey, USA. hirase@axon.rutgers.edu
Qian
Lifen
L
Barthó
Peter
P
Buzsáki
György
G
D000814:Aniline Compounds / Q000494:pharmacology; D000818:Animals; D001253:Astrocytes / Q000166:cytology* / Q000378:metabolism; D001921:Brain / Q000378:metabolism; D002118:Calcium / Q000378:metabolism; D020013:Calcium Signaling; D002450:Cell Communication; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D004594:Electrophysiology; D005260:Female; D005456:Fluorescent Dyes / Q000494:pharmacology; D007150:Immunohistochemistry; D008297:Male; D018613:Microscopy, Confocal; D018715:Microscopy, Video; D008954:Models, Biological; D009457:Neuroglia / Q000378:metabolism; D009474:Neurons / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D015398:Signal Transduction; D014966:Xanthenes / Q000494:pharmacology
D000814:Aniline Compounds; C409648:Fluo 4; D005456:Fluorescent Dyes; D014966:Xanthenes; D002118:Calcium