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Updated: Sep 28, 2026

Isolation of Human Atrial Myocytes for Simultaneous Measurements of Ca2+ Transients and Membrane Currents
Published on: July 3, 2013
[Inotropic effect of strophanthin in combination with calcium on the heart muscle]
Abstract:
The effect of strophanthine-g and its combination with different concentrations of calcium in Tyrode solution was studied in guinea-pig auriculi atrii contracting under the effect of isometric electric stimulation. Addition to Tyrode solution of strophanthine-g combined with calcium promoted the reduction of the positive inotropic effect of the former substance. During perfusion of the muscles with Tyrode solutions containing no calcium, the maintenance of the contractile function of the muscles is secured adequately enough by addition of strophanthine-g combined with low concentrations of calcium. Combinations of the cardiosteroid and calcium calculated on the basis of the stability constants of their complexes appeared effective. It is inferred that cardiosteroids should be combined with small amounts of calcium in order to attain a positive inotropic effect.
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