Abstract
In the previous paper (1), it has been reported that the continuous reduction of the net loss of K ions from muscles soaking in K free medium can be maintained only when the external Na ions are present. This fact indicates that the constant rate of the net loss of K ions is sustained by the constancy of K-Na interchange rate. Harris and Sjodin (2) have stated that K ion exchange has to be distinguished from net movement and the processes can be measured separately by choice of suitable conditions. It is possible to obtain information on membrane structure from the experimental data of the ionic behaviour across the cell membrane. Among the various kinds of movements of ions, the outward movement of K ions in K free medium has been studied in order to clarify whether the outward K ion movement is completely passive in nature; in other words, the purpose of this study is to discover the law governing the diffusion of K ions from an isolated sartorius muscle into K free bathing solution. This report is concerned with the results of studies of the mechanism of the net loss of K ions in K free medium.
