Calcium‐sodium antagonism on the frog's heart: a voltage‐clamp study.

@article{Benninger1976CalciumsodiumAO,
  title={Calcium‐sodium antagonism on the frog's heart: a voltage‐clamp study.},
  author={C. Benninger and H. M. Einw{\"a}chter and Hans G. Haas and R. Kern},
  journal={The Journal of Physiology},
  year={1976},
  volume={259}
}
1. In double sucrose‐gap voltage‐clamped frog atrial fibres the influence of [Ca]o and [Na]o on membrane current and contraction was investigated. 2. The slow (secondary) inward current varied with [Ca]o but was almost insensitive to changes in [Na]o. In contrast, the phasic (transient) contraction initiated by the slow inward current was affected by both [Ca]o and [Na]o. 3. With moderate changes of [Ca]o and [Na]o from normal, the strength of phasic contraction at a given depolarization… Expand
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