Measurement of reversal potential of Na+-Ca2+ exchange current in single guinea-pig ventricular cells

The Journal of Physiology
T EharaA Noma

Abstract

1. To identify the Na+- or Ca2+-induced current as Na+-Ca2+ exchange current and to determine the stoichiometry of the Na+-Ca2+ exchange, the reversal potential was measured in a wide range of external Na+ [( Na+]o) or Ca2+ [( Ca2+]o) concentrations. The Na+- or Ca2+-induced current was recorded in single ventricular cells enzymatically dispersed from guinea-pig hearts, using the technique of whole-cell voltage clamp combined with internal perfusion. 2. In the presence of 10-40 mM-Na+ and 55-803 nM-Ca2+ in the internal solution, an increase of [Ca2+]o from 0.1 to 0.5-20 mM or an increase of [Na+]o from 30 to 50-140 mM induced an extra current associated with an increase in membrane conductance. The reversal potential of these extra currents was determined from an intersection of the current-voltage (I-V) relations obtained in the absence and presence of a Na+-Ca2+ exchange blocker, Ni2+ (2 mM). 3. Ba2+ in the external solution failed to induce the extra current, but inhibited the background conductance having a reversal potential at around 0 mV. Thus, 1 mM-Ba2+ was added to all external solutions, so that a change in the background current was minimized during application of Ca2+ or Ni2+. 4. The relation between [Ca2+]o and amp...Continue Reading

Citations

Feb 12, 2011·Cellular and Molecular Neurobiology·Julio C SánchezLina De Los Reyes
Feb 1, 1990·The Journal of Membrane Biology·L Lagnado, P A McNaughton
Jan 1, 1990·Pflügers Archiv : European journal of physiology·K Yasui, J Kimura
Jan 1, 1989·Progress in Biophysics and Molecular Biology·P P Schnetkamp
Sep 1, 1990·Acta Physiologica Scandinavica·P Arlock, B Wohlfart
Nov 29, 2002·The Journal of Physiology·Masamitsu HinataJunko Kimura
Jan 1, 1991·Annals of the New York Academy of Sciences·P P SchnetkampR T Szerencsei
Jan 1, 1991·Annals of the New York Academy of Sciences·P A McNaughton
Jan 1, 1991·Annals of the New York Academy of Sciences·J H BridgeT K Chin
Jan 1, 1991·Annals of the New York Academy of Sciences·D C GadsbyM Nakao
Apr 15, 1996·Annals of the New York Academy of Sciences·J Kimura
Feb 24, 2001·The Journal of Physiology·Y FujiokaS Matsuoka
Aug 4, 2007·Progress in Neurobiology·Tamás L Török
Feb 17, 2007·Annals of the New York Academy of Sciences·Donald M Bers, Kenneth S Ginsburg
Sep 11, 2004·Journal of Pharmacological Sciences·Masamitsu Hinata, Junko Kimura
Feb 21, 2007·Cellular Physiology and Biochemistry : International Journal of Experimental Cellular Physiology, Biochemistry, and Pharmacology·Eva CagideLuis M Botana
Nov 16, 2012·Chemical Reviews·Mark A ZaydmanJianmin Cui
Oct 1, 1995·Journal of Cardiovascular Electrophysiology·B SzaboR Lazzara
Jun 23, 2006·Cellular Physiology and Biochemistry : International Journal of Experimental Cellular Physiology, Biochemistry, and Pharmacology·M Carmen LouzaoLuis M Botana
Sep 1, 1993·Clinical Physiology·B Wohlfart, P Arlock
Jan 1, 1991·Annals of the New York Academy of Sciences·M B Cannell
Sep 18, 2004·Circulation Research·David A Eisner, Karin R Sipido

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