Primary Pathways of Intracellular Ca2+ Mobilization by Nanosecond Pulsed Electric Field

Authors

Iurii Semenov, Old Dominion UniversityFollow
Shu Xiao, Old Dominion UniversityFollow
Andrei G. Pakhomov, Old Dominion UniversityFollow

Document Type

Article

Publication Date

2013

Publication Title

Biochimica et Biophysica Acta: Biomembranes

Volume

1828

Issue

3

Pages

981-989

DOI

10.1016/j.bbamem.2012.11.032

Abstract

Permeabilization of cell membranous structures by nanosecond pulsed electric field (nsPEF) triggers transient rise of cytosolic Ca²⁺ concentration ([Ca²⁺]_i), which determines multifarious downstream effects. By using fast ratiometric Ca²⁺ imaging with Fura-2, we quantified the external Ca²⁺ uptake, compared it with Ca²⁺ release from the endoplasmic reticulum (ER), and analyzed the interplay of these processes. We utilized CHO cells which lack voltage-gated Ca²⁺ channels, so that the nsPEF-induced [Ca²⁺]_i changes could be attributed primarily to electroporation. We found that a single 60-ns pulse caused fast [Ca2+]_i increase by Ca²⁺ influx from the outside and Ca²⁺ efflux from the ER, with the E-field thresholds of about 9 and 19 kV/cm, respectively. Above these thresholds, the amplitude of [Ca²⁺]_i response increased linearly by 8-10 nM per 1 kV/cm until a critical level between 200 and 300 nM of [Ca²⁺]_i was reached. If the critical level was reached, the nsPEF-induced Ca²⁺ signal was amplified up to 3000 nM by engaging the physiological mechanism of Ca²⁺-induced Ca²⁺-release (CICR). The amplification was prevented by depleting Ca²⁺ from the ER store with 100 nM thapsigargin, as well as by blocking the ER inositol-1,4,5-trisphosphate receptors (IP₃R) with 50 μM of 2-aminoethoxydiphenyl borate (2-APB). Mobilization of [Ca²⁺]_i; by nsPEF mimicked native Ca²⁺ signaling, but without preceding activation of plasma membrane receptors or channels. NsPEF stimulation may serve as a unique method to mobilize [Ca²⁺]i and activate downstream cascades while bypassing the plasma membrane receptors. (C) 2012 Elsevier B.V. All rights reserved..

Comments

Web of Science: "Free full-text from publisher -- gold open access."

Original Publication Citation

Semenov, I., Xiao, S., & Pakhomov, A. G. (2013). Primary pathways of intracellular Ca²⁺ mobilization by nanosecond pulsed electric field. Biochimica et Biophysica Acta: Biomembranes, 1828(3), 981-989. doi:10.1016/j.bbamem.2012.11.032

Repository Citation

Semenov, Iurii; Xiao, Shu; and Pakhomov, Andrei G., "Primary Pathways of Intracellular Ca2+ Mobilization by Nanosecond Pulsed Electric Field" (2013). Bioelectrics Publications. 178.
https://digitalcommons.odu.edu/bioelectrics_pubs/178

ORCID

0000-0002-0302-1355 (Semenov), 0000-0002-0375-8373 (Xiao)