Vinculin expression in MC3T3-E1 cells in response to mechanical stimulus.

Loading frequency is known to influence the expression of the focal adhesions of the adherent cells. A small cyclical tensile force was transmitted to mouse pre-osteoblast MC3T3-E1 cells through PDMS substrates of varying stiffness. Changes in cell behavior with respect to proliferation and characteristics of focal adhesions were quantified through immunofluorescence labeling of vinculin. Amount of inactive vinculin was higher on substrates subjected to cyclic stimulation when compared with the results of the static substrates, whereas the number and area of focal adhesion points underwent a reduction. Inactive vinculin appears as a cloud in the cytoplasm in the vicinity of the nucleus.