Measurement of active ion transport in man. Utilizing intact human erythrocytes

Alterations in ion transport have been implicated in the pathogenesis of several disease states. Methods of studying ion transport, however, are rather tedious, time consuming and not well defined in terms of kinetics and reproducibility. This paper describes a rapid, simple method of examining ion transport in intact human erythrocytes utilizing 86 rubidium as a tracer. Twelve normal subjects were studied utilizing this method. Kinetic studies were performed from which maximal velocity (V max), a substrate concentration required to achieve half-maximal activity (Km), and a measure of the Ouabain sensitive component were determined for each subject and for the population. Additionally, five subjects underwent a repeat study at varying intervals up to 11 weeks. The results proved to be highly reproducible for each subject. It is suggested that the present technique offers not only speed and simplicity but yields kinetic data that is highly reproducible. Such advantages would make the techniques described ideal for studies desiring to compare age matched controls to subjects with intercurrent disease