Na+ current and Ca2+ release from the sarcoplasmic reticulum during action potentials in guinea-pig ventricular myocytes

The Journal of Physiology
K R SipidoA J Pappano

Abstract

1. Ca2+ release from the sarcoplasmic reticulum (SR) was examined in enzymatically isolated single guinea-pig ventricular myocytes by monitoring [Ca2+]i with fura-2 during whole-cell recording of action potentials at room temperature (23-25 degrees C). Modulation of Ca2+ release by the Na+ current (INa) was studied by manipulating Na+ influx through the Na+ channel. 2. For a comparable Ca2+ loading of the SR, brief hyperpolarizing currents applied at the peak of the action potential increased Ca2+ release, while depolarizing pulses had the opposite effect. Similar currents applied before the action potential did not affect Ca2+ release. 3. Application of tetrodotoxin (TTX; 60 microM) moderately reduced Ca2+ release from the SR, but this effect was delayed in comparison with the immediate block of INa. An early effect of TTX was to increase Ca2+ release. 4. Replacement of Na+ with Li did not reduce Ca2+ release, but led to a progressive increase in Ca2+ release, resulting in spontaneous activity. 5. Ca2+ channel blockers (CdCl2, 100 microM; nisoldipine, 20 microM; or nifedipine, 20 microM) drastically reduced Ca2+ release from the SR. 6. Voltage clamp experiments confirmed that TTX blocked INa and its associated [Ca2+]i transien...Continue Reading

Citations

Jan 16, 2003·The Journal of Physiology·Yong G WangStephen L Lipsius
Dec 11, 2008·Current Problems in Cardiology·Guy KatzMichael Eldar
Aug 4, 2007·Progress in Neurobiology·Tamás L Török
Mar 28, 2007·Heart Failure Clinics·Luis F SantanaW Jonathan Lederer
Oct 9, 2012·Heart Rhythm : the Official Journal of the Heart Rhythm Society·Przemysław B RadwańskiSteven Poelzing
May 19, 2011·Journal of Molecular and Cellular Cardiology·M B Cannell, Cherrie H T Kong
May 13, 2014·Lancet Neurology·David L H Bennett, C Geoffrey Woods
Nov 14, 2012·Autonomic Neuroscience : Basic & Clinical·John H Schild, Diana L Kunze
Jun 24, 2011·Cardiovascular Research·Przemysław B Radwański, Steven Poelzing
Dec 30, 2014·Cardiovascular Research·Przemysław B RadwańskiSándor Györke
Jan 24, 2002·Nature·Donald M Bers
Oct 12, 2012·Pflügers Archiv : European journal of physiology·Peter LeeChristian Bollensdorff
Jan 31, 2020·Circulation Research·David A EisnerDavid C Hutchings
Oct 3, 2002·Neurogastroenterology and Motility : the Official Journal of the European Gastrointestinal Motility Society·Y OuG Farrugia
Jan 11, 2005·Journal of Applied Physiology·Janny BøkenesOle M Sejersted
Nov 8, 2014·American Journal of Physiology. Regulatory, Integrative and Comparative Physiology·Caroline CrosFabien Brette
Nov 15, 1997·The American Journal of Physiology·T SaekiA J Pappano
Apr 25, 2000·American Journal of Physiology. Heart and Circulatory Physiology·G R FerrierS E Howlett
Apr 12, 2001·American Journal of Physiology. Heart and Circulatory Physiology·G R Ferrier, S E Howlett
Oct 26, 2010·American Journal of Physiology. Heart and Circulatory Physiology·Cynthia GershomeGlen F Tibbits
Oct 12, 2010·American Journal of Physiology. Heart and Circulatory Physiology·Min DongHong-Sheng Wang
Aug 13, 1999·The American Journal of Physiology·J A Wasserstrom, A M Vites
Sep 18, 2021·The Journal of Physiology·Karin R Sipido, David A Eisner

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