A calcium requirement for movement of cultured cells.

When calcium is removed from culture medium, motility of cultured cells is decreased. The effect is rapid, reversible and pronounced. Decreased motility is observed with normal mouse Balb/c 3T3 cells, mouse L929 cells, rat kidney fibroblasts and chick embryo fibroblasts. The calcium dependence of movement can be observed both with individual cells and with the movement of the margin of a monolayer into a wound. Magnesium will not substitute for calcium to maintain motility. Strontium will substitute, but is not as effective as calcium for maintaining cell movement. Low concentrations of the divalent cation ionophore A23187 (0.5-1 micron) partially reverse the reduced migration observed at low calcium concentrations. These results are consistent with the hypothesis that movement of non-muscle cells occurs through mechanisms similar to those important in the contraction of muscle.