title: The effect of electrical deformation forces on the electropermeabilization of erythrocyte membranes in low- and high-conductivity media.
abstract: Electrical breakdown of erythrocytes induces hemoglobin release which increases markedly with decreasing conductivity of the pulse medium. This effect presumably results from the transient, conductivity-dependent deformation forces (elongation or compression) on the cell caused by Maxwell stress. The deformation force is exerted on the plasma membrane of the cell, which can be viewed as a transient dipole induced by an applied DC electric field pulse. The induced dipole arises from the free charges that accumulate at the cell interfaces via the Maxwell-Wagner polarization mechanism. The polarization response of erythrocytes to a DC field pulse was estimated from the experimental data obtained by using two complementary frequency-domain techniques. The response is very rapid, due to the highly conductive cytosol. Measurements of the electrorotation and electrodeformation spectra over a wide conductivity range yielded the information and data required for the calculation of the deformation force as a function of frequency and external conductivity and for the calculation of the transient development of the deformation forces during the application of a DC-field pulse. These calculations showed that (i) electric force precedes and accompanies membrane charging (up to the breakdown voltage) and (ii) that under low-conductivity conditions, the electric stretching force contributes significantly to the enlargement of "electroleaks" in the plasma membrane generated by electric breakdown.
authors.affiliation: Lehrstuhl für Biotechnologie, Biozentrum, Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany.
authors.forename: V L
authors.initials: VL
authors.lastname: Sukhorukov
authors.forename: H
authors.initials: H
authors.lastname: Mussauer
authors.forename: U
authors.initials: U
authors.lastname: Zimmermann
mesh_terms: D002463:Cell Membrane Permeability / Q000502:physiology; D004553:Electric Conductivity; D018274:Electroporation; D004907:Erythrocyte Deformability / Q000502:physiology*; D004910:Erythrocyte Membrane / Q000502:physiology*; D006461:Hemolysis / Q000502:physiology; D018056:Hemorheology; D006801:Humans