Protein synthesis by neuroblastoma cells is enhanced by exposure to burst-mode ultrasound cavitation

We observed enhancement of protein synthesis, compared to control cells, 24 h after exposing C1300 neuroblastoma cells (N2A) in rotating tubes at 37 degrees C to 1-MHz ultrasound tone bursts [1:1; durations from 6 to 600 ms; 3.4 W/cm2 spatial-peak burst-average intensity; 5 min total treatment duration (on + off periods)]. Protein synthesis was measured by uptake of 3H-leucine and normalized for cell proliferation by measured uptake of 14C thymidine. The similarity between results for enhanced cavitation-stimulated iodine-release reported by Ciaravino and our results for cellular protein synthesis suggests that cavitation causes this biological effect.