Boundary-element calculations for amplification of effects of low-frequency electric fields in a doublet-shaped biological cell

Abstract To examine the amplification of the effects of low-frequency electric fields due to the junction between the cells, the amplitude of transmembrane potential P TMP0 , the time-averaged normal stress σ n and the outward force density σ out on the shell-phase, and the squared intensity I ee of electric fields in the inner and the outer phases induced by uniform external ac fields were calculated with the boundary-element method for doublet-shaped cell models consisting of two spheres of the same size connected by the junction; the results were compared with those in a spherical model. When the external fields were parallel to the long axis of the doublet-shaped models, P TMP0 , σ n and σ out at the pole were greater than those in the spherical model, and σ out and I ee at the junction increased with the decrease in the junction-radius. The external fields perpendicular to the long axis caused I ee greater than that at the center of the spherical model and negative σ out , at the junction. The amplification of P TMP0 , σ n , σ out and I ee took place within restricted frequency-regions that could be specified by the characteristic frequencies for the frequency-dependence of the polarization factor of the models.