Potentiation by taurine of inotropic effect of strophanthin-K on guinea-pig isolated auricles

Abstract

Fresh guinea-pig auricles contain 39.4±4.2 mM of taurine per ml of intracellular water. When isolated, the auricles lose 15 per cent of their content in the Tyrode bath solution (30°C, pH 7.2–7.3, 97%O 2 +3% CO 2 ) during the first hour of incubation. After 5 hours of incubation taurine content is 70% of the initial value. At this time taurine content can be restored to its initial value by the addition of 8 mM taurine (final concentration) to the incubation fluid for 30 minutes; other times and concentrations have not been tested. Neither the taurine nor the homotaurine 8 mM concentrations affect the contractility or rate of the auricles. However, taurine, but not homotaurine, increases the contractileresponse to a fixed dose of strophanthin-K.