Abstract
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.
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Doerr, T., Denger, R. & Trautwein, W. Calcium currents in single SA nodal cells of the rabbit heart studied with action potential clamp. Pflugers Arch. 413, 599 (1989). https://doi.org/10.1007/BF00581808
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DOI: https://doi.org/10.1007/BF00581808