Calcium waves in retinal glial cells.
Calcium signals were recorded from glial cells in acutely isolated rat retina to determine whether Ca2+ waves occur in glial cells of intact central nervous system tissue. Chemical (adenosine triphosphate), electrical, and mechanical stimulation of astrocytes initiated increases in the intracellular concentration of Ca2+ that propagated at approximately 23 micrometers per second through astrocytes and Müller cells as intercellular waves. The Ca2+ waves persisted in the absence of extracellular Ca2+ but were largely abolished by thapsigargin and intracellular heparin, indicating that Ca2+ was released from intracellular stores. The waves did not evoke changes in cell membrane potential but traveled synchronously in astrocytes and Müller cells, suggesting a functional linkage between these two types of glial cells. Such glial Ca2+ waves may constitute an extraneuronal signaling pathway in the central nervous system.
Newman
E A
EA
Department of Physiology, University of Minnesota, 435 Delaware Street, SE, Minneapolis, MN 55455, USA.
Zahs
K R
KR
D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D001253:Astrocytes / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism*; D015220:Calcium Channels / Q000378:metabolism; D004558:Electric Stimulation; D006493:Heparin / Q000494:pharmacology; D066298:In Vitro Techniques; D053496:Inositol 1,4,5-Trisphosphate Receptors; D007700:Kinetics; D008564:Membrane Potentials; D009457:Neuroglia / Q000378:metabolism*; D010812:Physical Stimulation; D051381:Rats; D018160:Receptors, Cytoplasmic and Nuclear / Q000378:metabolism; D012160:Retina / Q000166:cytology* / Q000378:metabolism; D015398:Signal Transduction; D013268:Stimulation, Chemical; D019284:Thapsigargin / Q000494:pharmacology
D015220:Calcium Channels; D053496:Inositol 1,4,5-Trisphosphate Receptors; D018160:Receptors, Cytoplasmic and Nuclear; D019284:Thapsigargin; D000255:Adenosine Triphosphate; D006493:Heparin; D002118:Calcium