Stress fiber contributes to rat Schwann cell orientation under magnetic field

In this study, we investigated the role of cytoskeletons such as stress fibers on magnetic orientation of Schwann cells after 8-T magnetic field exposure, using an inhibitor of ROCK/Rho kinase (Y-27632), which selectively suppresses stress fiber and focal adhesion formation. Schwann cells were cultured from a dissected sciatic nerve of 2-d old Wistar rats. After the culturing, the cells were observed with a phase-contrast microscope and performed rhodamine phalloidin staining to visualize F-actin under the fluorescent microscope. Results show that under the influence of a strong magnetic field and upon exposure to 10-μM Y-27632, cells lose their ability to form stress fiber and their magnetic orientation was inhibited. This suggests that stress fiber formations are needed to respond to the magnetic orientation of Schwann cells and the anisotropic diamagnetic susceptibility of cytoskeletons is influenced by diamagnetic torque under a strong magnetic field, which in turn gradually contributes to the magnetic orientation of Schwann cells during cell division and proliferation. This observation provides a new aspect of the effect of static magnetic field on living cells.