Electrical excitability of roach ( Rutilus rutilus) ventricular myocytes: effects of extracellular K+, temperature, and pacing frequency.

@article{Badr2018ElectricalEO,
  title={Electrical excitability of roach ( Rutilus rutilus) ventricular myocytes: effects of extracellular K+, temperature, and pacing frequency.},
  author={Ahmed Badr and El-Sabry Abu-Amra and M. F. El-Sayed and Matti Vornanen},
  journal={American journal of physiology. Regulatory, integrative and comparative physiology},
  year={2018},
  volume={315 2},
  pages={
          R303-R311
        }
}
Exercise, capture, and handling stress in fish can elevate extracellular K+ concentration ([K+]o) with potential impact on heart function in a temperature- and frequency-dependent manner. To this end, the effects of [K+]o on the excitability of ventricular myocytes of winter-acclimatized roach ( Rutilus rutilus) (4 ± 0.5°C) were examined at different test temperatures and varying pacing rates. Frequencies corresponding to in vivo heart rates at 4°C (0.37 Hz), 14°C (1.16 Hz), and 24°C (1.96 Hz… 
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