Doering W, Belz G G
Klin Wochenschr. 1981 Jan 15;59(2):95-6. doi: 10.1007/BF01477289.
Co-administration of quinidine results in a marked increase in serum digoxin concentration (SDC). The implication of this increase in SDC in regard to an increased digoxin effect on the heart is controversial. The 86Rb-erythrocyte-assay represents a perfect model to study whether quinidine interferes with digoxin at the Na-K-ATPase (the so called glycoside receptor) and thus presumably with the inotropic effect of the glycoside. The inhibitory effect of digoxin (0-150 ng/ml) on the 86Rb-uptake was measured in the absence and presence of quinidine in therapeutic or higher concentrations (0-60 microgram/ml). Addition of quinidine produced no effect on digoxin-induced inhibition of Na-K-ATPase activity. Together with our clinical observations these results strongly suggest that the increased SDC during concomitant quinidine therapy actually reflects an increased digoxin effect on the heart.
奎尼丁的共同给药会导致血清地高辛浓度（SDC）显著升高。SDC的这种升高对心脏地高辛效应增强的影响存在争议。⁸⁶Rb红细胞测定法是一种理想的模型，用于研究奎尼丁是否在钠钾ATP酶（所谓的糖苷受体）处干扰地高辛，从而可能干扰糖苷的正性肌力作用。在不存在和存在治疗浓度或更高浓度（0 - 60微克/毫升）奎尼丁的情况下，测量地高辛（0 - 150纳克/毫升）对⁸⁶Rb摄取的抑制作用。添加奎尼丁对地高辛诱导的钠钾ATP酶活性抑制没有影响。结合我们的临床观察，这些结果强烈表明，在奎尼丁联合治疗期间SDC的升高实际上反映了地高辛对心脏的效应增强。
