DNA Synthesis in Cartilage Cells Is Stimulated by Oscillating Electric Fields

External oscillating electric fields (1166 volts per centimeter, 5 hertz) enhanced the incorporation of [ 3 H]thymidine into the DNA of chondrocytes isolated from the proliferative layer of embryonic (16 days) chick epiphysis. Verapamil or tetrodotoxin at 10 -6 M concentrations completely blocked the electric field effect. Tetracaine reduced the incorporation of [ 3 H]thymidine in both control and electrically stimulated cells. The findings support the hypothesis that Na + and Ca 2+ fluxes generated by the electrical perturbation trigger DNA synthesis in these cells.