title: Patchy accumulation of apical Na+ transporters allows cross talk between extracellular space and cell nucleus.
abstract: Intracellular Na+ activities and local current densities were measured in fused Madin-Darby canine kidney cells using Na+ and voltage-sensing microelectrodes. Na+ that enters the cell across the apical plasma membrane accumulates initially in the nucleoplasm, several seconds ahead of its appearance in the cell cytoplasm. The spatial distribution of Na+ currents, produced by a local superfusion of the cell surface, indicates a nonuniform, patchy accumulation of apical Na+ transporters in the vicinity of the nucleus. Such pathways for direct Na+ flux between extracellular space and cell nucleus could be potentially important for gene activation.
authors.affiliation: Department of Physiology, University of Würzburg, Federal Republic of Germany.
authors.forename: H
authors.initials: H
authors.lastname: Oberleithner
authors.forename: S
authors.initials: S
authors.lastname: Wünsch
authors.forename: S
authors.initials: S
authors.lastname: Schneider
mesh_terms: D000818:Animals; D001692:Biological Transport; D002451:Cell Compartmentation; D002467:Cell Nucleus / Q000378:metabolism*; D016764:Cell Polarity; D003593:Cytoplasm / Q000378:metabolism; D004285:Dogs; D004848:Epithelium / Q000378:metabolism; D005110:Extracellular Space / Q000378:metabolism*; D066298:In Vitro Techniques; D007668:Kidney / Q000166:cytology; D012964:Sodium / Q000378:metabolism*; D015222:Sodium Channels / Q000378:metabolism*
chemical_list: D015222:Sodium Channels; D012964:Sodium