Analysis of Inhomogeneous Static Magnetic Field-Induced Antinociceptive Activity in Mice

The effect of inhomogeneous static magnetic field (SMF) on visceral pain elicited by the intraperitoneal injection of 0.6% acetic acid (writhing test) was studied in mice in an environment, where animals could freely move. 30 min, whole-body exposure of mice to SMF (permanent NdFeB N50 grade 10× 10mm cylindrical magnets with alternating poles) following the nociceptive challenge resulted in a 74% inhibition of the pain reaction (p < 0.001). With the help of several inhomogeneous SMF configurations, where magnets were grouped in partitions and a 2D model of ambulation, motion-induced electric current density, MR-equivalent switching, and slew rate were estimated. Their potential contribution to peripheral nerve stimulation is discussed in correlation to pain inhibition.