MORPHOLOGICAL RESPONSE OF MAMMALIAN-CELLS TO PULSED AC FIELDS

A newly developed method of detecting morphology and morphological cha nges of adherent mammalian cells cultured on thin film gold electrodes (electrical cell-substrate impedance sensing) has been used to measur e the response of cells to external electrical stimuli. When sufficien tly high ac voltage pulses were applied, the impedance of the cell lay er changed reproducibly, indicating morphological changes in the cell layer, as no such impedance changes were seen with cell-free electrode s. The response increased with increasing voltage pulses and was disti nct far different cell types. The threshold voltage across the cell la yer causing an observable change was found to be of the order of 0.1 V , which is higher than that reported by others using de fields. In cer tain cases, it was found that the impedance of the cell layer decrease d upon pulsation and then started to recover, but decreased again befo re finally recovering. This suggests that two different events cause a drop in impedance of the cell layer when the adherent mammalian cells are transiently exposed to an external electrical field.