Abstract
Over a certain range of calcium concentrations, from about half to twice the normal concentration, there is a linear relation between the logarithm of the external calcium concentration and the force of cardiac contractions. Furthermore, there is very little hysteresis, so that when the calcium concentration is returned to normal for a second time the force of contraction is similar to what it was originally. This effect can, therefore, be used as a simple and convenient preliminary screening test for new drugs, to see whether they have calcium-antagonist activity (Fig. 1).
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References
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© 1980 Springer-Verlag Berlin-Heidelberg
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Vaughan Williams, E.M. (1980). Calcium Currents Mediating Inotropic and Chronotropic Effects in Mammalian Cardiac Muscle. In: Fleckenstein, A., Roskamm, H. (eds) Calcium-Antagonismus. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-67595-9_7
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DOI: https://doi.org/10.1007/978-3-642-67595-9_7
Publisher Name: Springer, Berlin, Heidelberg
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