Calcium currents in single SA nodal cells of the rabbit heart studied with action potential clamp

  • Th. Doerr
  • R. Denger
  • W. Trautwein
Excitable Tissues and Central Nervous Physiology


With a new method called “Action Potential-Clamp” (APC) we studied in single SA nodal cells the contribution of both transient and long lasting calcium currents (L-type and T-type) to the action potential. Action potentials were recorded by a computer and a representative cycle was subsequently repetitively replayed to the same cell under voltage clamp. Blockade of the L-type calcium current (D600) or T-type calcium current (nickel) revealed the quantitative and time related contributions of these currents to the action potential, since the blocked current is compensated by the clamp amplifier.

Key words

Rabbit heart SA nodal cells Ca2+ currents Action potential clamp 


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Copyright information

© Springer-Verlag 1989

Authors and Affiliations

  • Th. Doerr
    • 1
  • R. Denger
    • 1
  • W. Trautwein
    • 1
  1. 1.II. Physiologisches InstitutUniversität des SaarlandesHomburg/SaarFederal Republic of Germany

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