The Effects of X-irradiationin Vitroon the Transport of Potassium Ions in Thymocytes

Abstract
Thymocytes were exposed to x-radiation in the dose-range 0·2 to 20 krads in vitro. The decrease in intracellular potassium levels produced is attributed to two separate mechanisms : inhibition of active transport and increased membrane permeability. Evidence for both mechanisms is sought by 42K tracer studies and flame photometry. The influence of ouabain, low-temperature incubation, and choline chloride mediums are studied, both in relation to total potassium changes and in the inhibition of influx rates of potassium ions.