title: High electrical field effects on cell membranes.
abstract: Electrical charging of lipid membranes causes electroporation with sharp membrane conductance increases. Several recent observations, especially at very high field strength, are not compatible with the simple electroporation picture. Here we present several relevant experiments on cell electrical responses to very high external voltages. We hypothesize that, not only are aqueous pores created within the lipid membranes, but that nanoscale membrane fragmentation occurs, possibly with micelle formation. This effect would produce conductivity increases beyond simple electroporation and display a relatively fast turn-off with external voltage. In addition, material loss can be expected at the anode side of cells, in agreement with published experimental reports at high fields. Our hypothesis is qualitatively supported by molecular dynamics simulations. Finally, such cellular responses might temporarily inactivate voltage-gated and ion-pump activity, while not necessarily causing cell death. This hypothesis also supports observations on electrofusion.
authors.affiliation: Frank Reidy Research Center for Bioelectrics 830 Southampton Ave., Suite 5100, Norfolk, VA 23510, United States.
authors.forename: U
authors.initials: U
authors.lastname: Pliquett
authors.forename: R P
authors.initials: RP
authors.lastname: Joshi
authors.forename: V
authors.initials: V
authors.lastname: Sridhara
authors.forename: K H
authors.initials: KH
authors.lastname: Schoenbach
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000737:chemistry / Q000502:physiology* / Q000528:radiation effects*; D002463:Cell Membrane Permeability / Q000502:physiology* / Q000528:radiation effects*; D003198:Computer Simulation; D004307:Dose-Response Relationship, Radiation; D004574:Electromagnetic Fields; D018274:Electroporation / Q000379:methods*; D006801:Humans; D019169:Jurkat Cells; D008051:Lipid Bilayers / Q000737:chemistry / Q000378:metabolism* / Q000528:radiation effects; D051379:Mice; D008812:Mice, Hairless; D008954:Models, Biological; D011829:Radiation Dosage
chemical_list: D008051:Lipid Bilayers