Figure 1.

V_m response in a single cell to an electric field. (a) Schematic of an elongated cell in an electric field. An electric field (E) creates a gradient of extracellular potential (V_e). Dashed lines indicate isopotential lines. Because of the relatively high impedance of the cell membrane and the short cell length, negligible amounts of current pass through the membrane, and the intracellular voltage (V_i) remains nearly constant throughout the cell. (b) Spatial profiles of V_e, V_i, and transmembrane potential (V_m) along the cell.