Pulsed electric current enhances the phorbol ester induced oxidative burst in human neutrophils

Oxidative burst (OB) response in human neutrophils, measured with chemiluminescence (CL), has been used to determine whether pulsed electric current (PEC) might induce a functional response in these electrically nonexcitable cells, and also whether it might modify cellular response to tumor-promoting phorbol ester (PMA). Five minutes of PEC treatment caused no significant changes in neutrophil CL levels in HBSS (1.2 mM Ca2+ concentration) as well as in HBSS-EGTA, where the extracellular Ca2+ concentration was reduced to less than 30 nM. The CL level of PMA-activated neutrophils in HBSS was 52% higher than in HBSS-EGTA. In HBSS the CL level, after the combined PMA and PEC treatment, was 53% higher than in PMA-alone-treated neutrophils. Activation of the OB in HBSS-EGTA with PMA and PEC was 13% higher than in solely PMA treated neutrophils. The results suggest that in neutrophil OB response, the PEC effect is closely related with cellular calcium mobilization, since depletion of extracellular Ca2+ decreased the PEC effect.