RESUMEN
Objective To observe the effects of permanent magnetic fields with different magnetic inductions on oxidative damage to human brain microvascular endothelial cells (HBMECs) under normal and hypoxic conditions. Methods HBMECs were cultured in vitro under normal and hypoxic conditions,then divided into a control group and groups receiving magnetic induction at 8.1,16.5,20.3,26.0,27.3,62.5,110.7 and 215.6 mT.Changes in superoxide dismutase (SOD) activity and malondialdehyde (MDA) content in each group were measured 72 h after exposure to the magnetic fields. Results Under normal conditions the SOD activities of the magnetic groups were not significantly different from that of the control group. Only the MDA content of the 215.6 mT group was statistically different (slightly higher) than that of the control group (P ＜ 0.05 ).Under hypoxic conditions,there was again no statistically significant difference in SOD activity,but the MDA content of the 110.7 mT group was significantly lower. Conclusions Under normal conditions,a 215.6 mT permanent magnetic field has an effect on MDA in HBMECs; under hypoxic conditions a 110.7 mT permanent magnetic field has such an effect.