Lanthanum Chloride Promoted Proliferation with Enhanced S‐phase Entry and Inhibited Potassium Currents of NIH 3T3 Cells

The effects of La 3+ on proliferation, cell cycles, apoptosis and ion channels were investigated in mouse embryo fibroblast NIH 3T3 cells and its possible mechanisms were explored. Our data showed that La 3+ promoted cell proliferation with increased S‐phase entry and inhibited the outward potassium currents in a concentration‐dependent manner in NIH 3T3 cells. La 3+ and Ca 2+ had synergistic effect on cell proliferation and cell cycles. It showed that Ca 2+ was needed for La 3+ ‐promoted cell cycle progression. Using the whole‐cell voltage‐clamp technique, we found that La 3+ blocked the outward potassium current in a concentration‐dependent manner in NIH 3T3 cells. Lanthanum ions can increase intracellular Ca 2+ concentration through inhibition of potassium currents, which induce a series of physiological changes and improve proliferation of cells. This may be one of the molecular mechanisms of lanthanum ions induced cell proliferation. The present work provides a new perspective for understanding the biological and toxicological effects of lanthanum.