Intravenous or oral administrations of erythromycin in humans have been reported to induce excessive prolongation of QT interval and even cause polymorphic ventricular tachycardia and torsade de points. Inthis study, ...Intravenous or oral administrations of erythromycin in humans have been reported to induce excessive prolongation of QT interval and even cause polymorphic ventricular tachycardia and torsade de points. Inthis study, we evaluated the effects of erythromycin on Ik, through direct measurement of the fast inactivationcurrent by using a two-pulses protocol. The results showed that erythrornycin 100 μmol/L restrained the fastinactivation current (P<0. 05), and its effects were both dose--dependent and voltage-dependent. As a result. the time course of erythromycin on the inactivation current was slow and washout was difficult. Our results expectedly may explain the reason why erythromycin slows the repolarization of action potential,lengthens QT interval, and causes torsade de points in humans.展开更多
文摘Intravenous or oral administrations of erythromycin in humans have been reported to induce excessive prolongation of QT interval and even cause polymorphic ventricular tachycardia and torsade de points. Inthis study, we evaluated the effects of erythromycin on Ik, through direct measurement of the fast inactivationcurrent by using a two-pulses protocol. The results showed that erythrornycin 100 μmol/L restrained the fastinactivation current (P<0. 05), and its effects were both dose--dependent and voltage-dependent. As a result. the time course of erythromycin on the inactivation current was slow and washout was difficult. Our results expectedly may explain the reason why erythromycin slows the repolarization of action potential,lengthens QT interval, and causes torsade de points in humans.