Rate of damage of MAGIC-5 cells in response to electrical stimulation. MAGIC-5 cells were cultured for 3 h at 37°C on PLL-coated ITO electrodes and then stimulated by a d.c. potential of 1.0 V (vs. Ag/AgCl) for 3 to 15 min. The cells were stained with 0.4% trypan blue dye for 5 min. More than 1,000 cells were counted under a microscope. Data represent the geometric mean ± standard deviation of duplicate determinations.