Characteristics of Delayed Rectifier Potassium Channels Exposed to 3 mT Static Magnetic Field

To investigate the characteristics of delayed rectifier potassium channel of cells under moderate intensity static magnetic field, the delayed rectifier potassium channel currents (I_K) of acutely isolated mouse prefrontal cortex pyramidal neurons were examined. I_K was measured and recorded after the neurons were exposed to 3 mT static magnetic field for 15,30, and 60 min. The results demonstrated that the 3 mT static magnetic field can change the characteristics of delayed rectifier potassium channel and reduce the amplitudes of I_K. The maximum activated current densities of control group and 30 min exposure group were respectively 173.61 ± 30.68 pA/pF and 111.80 ± 17.17 pA/pF (n = 10, P <; 0.05). The half-activation voltage of the activation curves changed from -1.08 ± 2.17 mV to 10.63 ± 1.51 mV (n = 10, P <; 0.05) and the slope factor changed from 22.26 ± 2.99 mV to 17.90 ± 1.85 mV (n = 10, P <; 0.05). No change was noted in the inactivation process. The results show that moderate-intensity static magnetic field can change the characteristics of delayed rectifier potassium channel on the cell membrane, and further it may affect the physiological functions of neurons.