Figure 1.

(A) Polarization of cells based on cell type. Excitable cell such as neurons have a membrane potential of -90 mV. Non-excitable cells such as HMEC: Human Mammary Epithelial Cell and MCF7: Estrogen-receptor-positive breast cancer cell line are at -60 mV and -13 mV respectively. (B) Depolarized cell state (left) indicated by a more positive charge in the cytoplasm relative to the extracellular space. Hyperpolarized cell state (right) indicated by a less positive charge in the cytoplasm relative to the extracellular space.