HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

J. Biol. Chem., Vol. 279, Issue 22, 22964-22972, May 28, 2004

This Article Full Text Full Text (PDF) All Versions of this Article: 279/22/22964    most recent M311135200v1 Submit a Letter to Editor Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via Google Scholar Google Scholar Articles by White, J. A. Articles by Beebe, S. J. Search for Related Content PubMed PubMed Citation Articles by White, J. A. Articles by Beebe, S. J. Social Bookmarking                      What's this?

Stimulation of Capacitative Calcium Entry in HL-60 Cells by Nanosecond Pulsed Electric Fields^*

Jody A. White, Peter F. Blackmore, Karl H. Schoenbach¶, and Stephen J. Beebe||**

From the Biomedical Sciences Program, Old Dominion University and Eastern Virginia Medical School, Department of Physiological Sciences, Eastern Virginia Medical School, ^¶Center for Bioelectrics, Old Dominion University, Norfolk, Virginia 23529, and ^||Center for Pediatric Research, Eastern Virginia Medical School and Children's Hospital of the King's Daughters, Norfolk, Virginia 23510

Nanosecond pulsed electric fields (nsPEFs) are hypothesized to affect intracellular structures in living cells providing a new means to modulate cell signal transduction mechanisms. The effects of nsPEFs on the release of internal calcium and activation of calcium influx in HL-60 cells were investigated by using real time fluorescent microscopy with Fluo-3 and fluorometry with Fura-2. nsPEFs induced an increase in intracellular calcium levels that was seen in all cells. With pulses of 60 ns duration and electric fields between 4 and 15 kV/cm, intracellular calcium increased 200–700 nM, respectively, above basal levels (100 nM), while the uptake of propidium iodide was absent. This suggests that increases in intracellular calcium were not because of plasma membrane electroporation. nsPEF and the purinergic agonist UTP induced calcium mobilization in the presence and absence of extracellular calcium with similar kinetics and appeared to target the same inositol 1,4,5-trisphosphate- and thapsigargin-sensitive calcium pools in the endoplasmic reticulum. For cells exposed to either nsPEF or UTP in the absence of extracellular calcium, there was an electric field-dependent or UTP dose-dependent increase in capacitative calcium entry when calcium was added to the extracellular media. These findings suggest that nsPEFs, like ligand-mediated responses, release calcium from similar internal calcium pools and thus activate plasma membrane calcium influx channels or capacitative calcium entry.

Received for publication, October 9, 2003 , and in revised form, March 2, 2004.

^* This work was supported by the Air Force Office of Scientific Research/Department of Defense MURI grant on Subcellular Responses to Narrowband and Wideband Radiofrequency Radiation (to S. J. B. and K. H. S.), the American Cancer Society (to S. J. B.), Jeffress Memorial Trust (to P. F. B.), the American Heart Association (to P. F. B.), Virginia affiliate, and the Virginia Commonwealth Health Research Board (to P. F. B.). The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

^** To whom correspondence should be addressed. Tel.: 757-668-6465; Fax: 757-668-6476; E-mail: sbeebe{at}chkd.com.

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?