Abstract
The effect of magnetic field on nitric oxide (NO) production of cultured human umbilical vein endothelial cells (HUVECs) was investigated. Static magnetic fields (30 mT, 300 mT) and an oscillating magnetic field (30 mT, 20 Hz) were applied to HUVECs for 0.5, 1 and 6 hours and intracellular NO was observed using a fluorescent indicator. There was no effect of the static magnetic field on the NO production of the HUVECs. In contrast, the NO production increased with applying the oscillating magnetic field for 0.5 hour. However, such an increase of NO production was not observed for 1 and 6 hours. We performed a separate experiment to clarify the mechanism of NO synthesis by using an inhibitor of calcium-independent activation of NO synthase. The inhibitor suppressed the increase of NO production caused by the oscillating magnetic field. It can be concluded that oscillating magnetic field may activate calcium-independent pathway of activation for NO synthase.