Ultrasound-induced changes in rates of influx and efflux of potassium ions in rat thymocytes in vitro

Abstract

Abstract It is demonstrated that the potassium content of rat thymocytes in vitro is decreased following exposure to 2W/cm 2 , 3MHz ultrasound for 40 min at 37°C, without inducing cell lysis or gross membrane damage. The abnormal values for potassium are maintained after completion of insonation. The changes are shown to arise from ultrasound-induced decreases in ion influx together with increases in potassium efflux. Recorded temperature changes in the media are shown to be insufficient to account for the observed decreases in cell potassium. The magnitude of cell potassium decrease at 3 MHz is shown to be similar in aerated and degassed water. Acoustic microstreaming either at the cell membrane of within the cell is suggested as the damage mechanism leading to ion flux changes.