Hoeschen R J
Recent Adv Stud Cardiac Struct Metab. 1976;9:345-53.
The reversal of digoxin effects by digoxin antibody (Ab) may be mediated by at least two mechanisms. First, the Ab may simply decrease the concentration of free digoxin in the perfusing medium, or second, the Ab may dislodge digoxin from its receptor. To pursue this problem, rabbit hearts were perfused for 20 min with Krebs-Henseleit solution (K-H) followed by a 30-min perfusion with [3H] digoxin in concentrations of 10(-7), 5x10(-7), and 10(-6) M. The hearts were then washed out with K-H alone or with K-H containing Ab. During washout the effluent was collected at 30-sec intervals and the concentration of [3H] digoxin measured in each sample. Washout was continued until the positive inotropic effect of digoxin had returned to its previous level. The [3H] digoxin washout curves were analyzed on the basis of statistical criteria and yielded three exponential components. During Ab washout the half-times t1/2 of these components were 0-25 +/- 0.07, 1.70 +/- 0.28, and 19.5 +/- 6.9 min, while during K-H washout the values were 0.28 +/- 0.02, 1.49 +/- 0.22, and 11.8 +/- 2.7. The decay of the inotropic effect of digoxin was similar during both washout conditions. The results indicate that the apparent tissue to perfusate concentration gradient for the washout of [3H] digoxin was not increased by Ab...
地高辛抗体（Ab）对地高辛效应的逆转可能至少由两种机制介导。第一，抗体可能只是降低灌注液中游离地高辛的浓度，或者第二，抗体可能使地高辛从其受体上解离下来。为了研究这个问题，用克雷布斯 - 亨塞尔特溶液（K - H）对兔心脏灌注20分钟，随后用浓度为10(-7)、5×10(-7)和10(-6)M的[3H]地高辛灌注30分钟。然后用单独的K - H溶液或含抗体的K - H溶液冲洗心脏。冲洗过程中，每隔30秒收集流出液，并测量每个样品中[3H]地高辛的浓度。冲洗持续进行，直到地高辛的正性肌力作用恢复到先前水平。根据统计标准分析[3H]地高辛的冲洗曲线，得出三个指数成分。在抗体冲洗过程中，这些成分的半衰期t1/2分别为0 - 25±0.07、1.70±0.28和19.5±6.9分钟，而在K - H冲洗过程中，其值分别为0.28±0.02、1.49±0.22和11.8±2.7分钟。在两种冲洗条件下地高辛正性肌力作用的衰减相似。结果表明，抗体并未增加[3H]地高辛冲洗时组织与灌注液之间明显的浓度梯度……
