Acid and alkaline phosphatase activity in bone following intense magnetic field irradiation of short duration.

Consideration of the biological effects of electromagnetic radiation is particularly important with regard to bone metabolism. Magnetic fields have been applied to the treatment of bone fractures, and similar fields are employed in the visualization of skeletal structures through magnetic resonance imaging (MRI). The present investigation addressed the effect of MRI-intensity (1 Tesla) magnetic fields on enzymatic indices of bone metabolism. Mice were exposed to intense static (direct current) magnetic fields for 30 min on each of 10 successive days. After this exposure regimen the primary spongiosum of the humerus was assayed for acid and alkaline phosphatase activity. No significant difference was detected in tissue levels of either enzyme in bones from control (n = 10), sham-exposed (n = 10), and magnetic field-exposed (n = 10) mice. These results suggested that the effects of magnetic field irradiation do not appear to involve modification of the activities of regulatory enzymes in bone.