Abstract
Measurements of the maximal rate of rise (\(\dot V_{\max } \)) of the action potential in cardiac Purkinje fibers were made at different intervals following an action potential or a long-duration depolarization. Recovery of\(\dot V_{\max } \) is fast after a short depolarization but is composed of a fast phase and a very slow phase (time constant order of 1 s) after a long-duration depolarization. The existence of a slow phase in the recovery explains the shift of the (\(\dot V_{\max } \) - Em) relationship to negative potentials in fibers with reduced resting potential.
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Saikawa, T., Carmeliet, E. Slow recovery of the maximal rate of rise (\(\dot V_{max} \)) of the action potential in sheep cardiac Purkinje fibers. Pflugers Arch. 394, 90–93 (1982). https://doi.org/10.1007/BF01108313
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DOI: https://doi.org/10.1007/BF01108313