Outward membrane currents activated in the plateau range of potentials in cardiac Purkinje fibres

@article{Noble1969OutwardMC,
  title={Outward membrane currents activated in the plateau range of potentials in cardiac Purkinje fibres},
  author={Denis Noble and Richard W. Tsien},
  journal={The Journal of Physiology},
  year={1969},
  volume={200}
}
1. The membrane currents in Purkinje fibres under voltage clamp conditions have been investigated in the range of potentials at which the action potential plateau occurs. The results show that in this range slow outward current changes occur which are quite distinct from the potassium current activated in the pace‐maker range of potentials. 
The dependence of plateau currents in cardiac Purkinje fibres on the interval between action potentials
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Reconstruction of the repolarization process in cardiac Purkinje fibres based on voltage clamp measurements of membrane current
TLDR
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References

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1. In normal Tyrode solution the initial inward sodium current which is produced in Purkinje fibres in response to a sudden depolarization is followed by a very slow change in current in an outwardExpand
The effect of subthreshold potentials on the membrane current in cardiac Purkinje fibres
1. In sodium‐containing solutions, up to 60% of the slow outward current in Purkinje fibres can be activated by depolarizations which are too small to activate the fast sodium conductance responsibleExpand
The kinetics and rectifier properties of the slow potassium current in cardiac Purkinje fibres
TLDR
It is concluded that virtually all of the slow outward current in Purkinje fibres is carried by potassium ions. Expand
Slow inactivation of currents in cardiac Purkinje fibres
  • H. Reuter
  • Chemistry, Medicine
  • The Journal of physiology
  • 1968
TLDR
This current could only be recorded in Na‐containing solution which strongly supports the view that the inactivation of sodium conductance (gNa) has a slow and incomplete component. Expand
The mechanism of oscillatory activity at low membrane potentials in cardiac Purkinje fibres
TLDR
The mechanism of oscillations at low membrane potentials in Purkinje fibres has been investigated using voltage clamp experiments using Voltage clamp experiments 1.1. Expand
Reconstruction of the repolarization process in cardiac Purkinje fibres based on voltage clamp measurements of membrane current
TLDR
The results of the voltage clamp experiments described in a preceding paper have been used to reconstruct the repolarization process in Purkinje fibres. Expand
The voltage dependence of the cardiac membrane conductance.
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TLDR
It is concluded that Johnson and Tille's results showing linear polarizing current-voltage relations obtained by passing current through the membrane from a microelectrode during the plateau of the rabbit ventricular action potential do not conflict with the Hodgkin-Huxley theory of electrical activity. Expand
Anomalous Rectification in the Squid Giant Axon Injected with Tetraethylammonium Chloride
TLDR
Experiments on fibers in an external medium of high potassium ion concentration demonstrate that injected tetraethylammonium chloride causes rectification of the instantaneous current-voltage curve for potassium by excluding outward current. Expand
The effect of the cardiac membrane potential on the rapid availability of the sodium‐carrying system
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TLDR
The present experiments were undertaken in order to look for a similar effect in mammalian Purkinje fibres by means of a feedback circuit the 'resting' potential could be chosen at will; its effect was observed on certain features of the action potential which are thought to be indicative of the sodium permeability, namely the upstroke velocity and the size of the 'overshoot'. Expand
Chloride ions and the membrane potential of Purkinje fibres
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TLDR
The results suggest that the contribution of chloride ions to the total membrane conductance is low in a resting fibre but increases when a fibre is depolarized. Expand
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