[Effect of adaptation to periodic hypoxia on bioelectric activity of cardiomyocytes and cardiac resistance to contractive and arrhythmogenic effects of excessive calcium].
The experiments with isolated hearts from the rats adaptive to a periodic exposure to hypoxia in the barochamber revealed a significant decrease in the contractile and arrhythmogenic effects of high Ca2+ concentrations. With low sodium solution, the contracture and the resting potential depression of cardiomyocytes in the cardiac papillary muscles turned to be less pronounced during adaptation. Increasing the concentration of Ca2+ in the washing solution resulted in lower resting potential, amplitude and duration of the action potential; hypoxic adaptation prevented the changes to a great extent. Whether the changes found may contribute to the anti-arrhythmic effect of periodic hypoxic adaptation is discussed in the paper.
Meerson
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Vovk
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D000200:Action Potentials / Q000187:drug effects / Q000502:physiology; D000222:Adaptation, Physiological / Q000502:physiology*; D000818:Animals; D002122:Calcium Chloride / Q000008:administration & dosage*; D005117:Cardiac Complexes, Premature / Q000517:prevention & control*; D000860:Hypoxia / Q000503:physiopathology*; D066298:In Vitro Techniques; D008297:Male; D008954:Models, Biological; D009200:Myocardial Contraction / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D013997:Time Factors
D002122:Calcium Chloride
Vliianie adaptatsii k periodicheskoĭ gipoksii na bioélektricheskuiu aktivnost' kardiomiotsitov i rezistentnost' serdtsa k kontrakturnomu i aritmogennomu éffektu izbytka kal'tsiia.