Activation of activator protein-1 in cells exposed to electrical stimulation of various parameters used in...

The aim of this study was to investigate the effect of electrical stimulation on activator protein-1 (AP-1) in recombinant liver cells. In order to elucidate the molecular effects of electrical stimulation on cells, AP-1 expression was detected by a luciferase assay. The parameters used were taken from clinical electroacupuncture (EA) therapy as follows: biphasic rectangular symmetrical pulses (frequency: 2, 10 and 100 Hz; pulse width: 50, 80, 130 and 250 microsec; intensity: 1, 2, 5 and 10 mA; time: 5, 10, 20 and 30 minutes). S (10% fetal bovine serum in medium), SF (serum free medium) and 12-O-tetradecanoylphorbol-13-acetate (TPA) treatment represented the experimental, negative and positive groups, respectively. We found that electrical stimulation with 10 Hz, a pulse width of 130 microsec, and a duration of 30 minutes gave a significant increase in AP-1 activity. In contrast, the intensity of the stimulation had no significant effect on AP-1 activity. In conclusion, our data suggest that electrical stimulation with an appropriate frequency, duration and pulse width could cause an increase in AP-1 activity in cells.