title: Optical probing of sodium dynamics in neurons and astrocytes.
abstract: Changes in intracellular Na(+) concentration underlie essential neurobiological processes, but few reliable tools exist for their measurement. Here we characterize a new synthetic Na(+)-sensitive fluorescent dye, Asante Natrium Green (ANG), with unique properties. This indicator was excitable in the visible spectrum and by two-photon illumination, suffered little photobleaching and located to the cytosol were it remained for long durations without noticeable unwanted effects on basic cell properties. When used in brain tissue, ANG yielded a bright fluorescent signal during physiological Na(+) responses both in neurons and astrocytes. Synchronous electrophysiological and fluorometric recordings showed that ANG produced accurate Na(+) measurement in situ. This new Na(+) indicator opens innovative ways of probing neuronal circuits.
authors.affiliation: Department of Cell Biology and Morphology, University of Lausanne, Rue du Bugnon 9, 1005 Lausanne, Switzerland. christophe.lamy@unil.ch
authors.forename: Christophe M
authors.initials: CM
authors.lastname: Lamy
authors.forename: Jean-Yves
authors.initials: JY
authors.lastname: Chatton
mesh_terms: D000200:Action Potentials / Q000502:physiology; D000465:Algorithms; D000818:Animals; D001253:Astrocytes / Q000378:metabolism*; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology; D003198:Computer Simulation; D055724:Electrophysiological Phenomena; D005456:Fluorescent Dyes; D066298:In Vitro Techniques; D007700:Kinetics; D051379:Mice; D008810:Mice, Inbred C57BL; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D009474:Neurons / Q000378:metabolism*; D018408:Patch-Clamp Techniques; D051381:Rats; D017207:Rats, Sprague-Dawley; D015203:Reproducibility of Results; D012964:Sodium / Q000378:metabolism*; D013003:Somatosensory Cortex / Q000378:metabolism
chemical_list: D005456:Fluorescent Dyes; D012964:Sodium