Skip directly to search Skip directly to A to Z list Skip directly to page options Skip directly to site content

NIOSHTIC-2 Publications Search

Search Results

Electric field-induced changes in agonist-stimulated calcium fluxes of human HL-60 leukemia cells.

Authors
Kim-YV; Conover-DL; Lotz-WG; Cleary-SF
Source
Bioelectromagnetics 1998 Sep; 19(6):366-376
NIOSHTIC No.
20024977
Abstract
The mechanism of biological effects of extremely-low-frequency electric and magnetic fields may involve induced changes of Ca2+ transport through plasma membrane ion channels. In this study we investigated the effects of externally applied, low-intensity 60 Hz electric (E) fields (0.5 V/m, current density 0.8 A/m2) on the agonist-induced Ca2+ fluxes of HL-60 leukemia cells. The suspensions of HL-60 cells received E-field or sham exposure for 60 min and were simultaneously stimulated either by 1 microM ATP or by 100 microM histamine or were not stimulated at all. After E-field or sham exposure, the responses of the intracellular calcium levels of the cells to different concentrations of ATP (0.2-100 microM) were assessed. Compared with control cells, exposure of ATP-activated cells to an E-field resulted in a 20-30% decrease in the magnitude of [Ca2+]i elevation induced by a low concentration of ATP (<1 microM). In contrast, exposure of histamine-activated HL-60 cells resulted in a 20-40% increase of ATP-induced elevation of [Ca2+]i. E-field exposure had no effect on non-activated cells. Kinetic analysis of concentration-response plots also showed that compared with control cells, exposure to the E-field resulted in increases of the Michaelis constant, Km, value in ATP-treated cells and of the maximal [Ca2+]i peak rise in histamine-treated HL-60 cells. The observed effects were reversible, indicating the absence of permanent structural damages induced by acute 60 min exposure to electric fields. These results demonstrate that low-intensity electric fields can alter calcium distribution in cells, most probably due to the effect on receptor-operated Ca2+ and/or ion channels.
Keywords
Calcium-compounds; Biological-effects; Magnetic-fields; Simulation-methods; Exposure-levels; Bioelectric-effects; Cell-cultures
Contact
David L. Conover, C-27, Division of Biomedical and Behavioral Science, National Institute for Occupational Safety and Health, 4676 Columbia Parkway, Cincinnati, OH 45226
CODEN
BLCTDO
Publication Date
19980901
Document Type
Journal Article
Fiscal Year
1998
NTIS Accession No.
NTIS Price
Issue of Publication
6
ISSN
0197-8462
NIOSH Division
DBBS
Source Name
Bioelectromagnetics
State
OH; VA
TOP