title: Measurement of single channel currents from cardiac gap junctions.
abstract: Cardiac gap junctions consist of arrays of integral membrane proteins joined across the intercellular cleft at points of cell-to-cell contact. These junctional proteins are thought to form pores through which ions can diffuse from cytosol to cytosol. By monitoring whole-cell currents in pairs of embryonic heart cells with two independent patch-clamp circuits, the properties of single gap junction channels have been investigated. These channels had a conductance of about 165 picosiemens and underwent spontaneous openings and closings that were independent of voltage. Channel activity and macroscopic junctional conductance were both decreased by the uncoupling agent 1-octanol.
mesh_terms: D000818:Animals; D002642:Chick Embryo; D004553:Electric Conductivity; D006168:Guinea Pigs; D006321:Heart / Q000196:embryology; D007365:Intercellular Junctions / Q000502:physiology*; D007473:Ion Channels / Q000166:cytology*; D009206:Myocardium / Q000166:cytology*; D051381:Rats
chemical_list: D007473:Ion Channels