Immunology and Cell Biology · 1960 · 24 citations · 0 references
MedicineCardiologyPhysiologyBioinstrumentationCell PolarityElectrophysiologyAction PotentialsBiopotential MeasurementCardiac Action PotentialsCardiac PhysiologyMuscle PhysiologyVentricular ElectrophysiologyCardiac Action Potential PhysiologyCardiac RepolarizationIntracellular Ventricular ElectrophysiologyVentricular Action PotentialsVentricular ExcitabilityVentricular Repolarization
SUMMARY The magnitude and time course of changes in polarisation resistance during the repolarisation phase of action potentials recorded from rabbit ventricular muscle have been measured with intracellular double‐barrelled microelectrodes. Action potentials from 74 fibres in 7 preparations have been examined. In all fibres, at some time during the repolarisation phase, the polarisation resistance was greater than the resting polarisation resistance. The mean maximum increase above the resting value was 1·63 (± 0·15 S.D.) times. The polarisation resistance remained constant even with large negative voltage displacements (60 mV). No evidence was found of regenerative repolarisation.