The effect of static magnetic fields on the rate of calcium/calmodulin-dependent phosphorylation of myosin light chain.

This study reports an attempt to confirm a published and well-defined biological effect of magnetic fields. The biological model investigated was the phosphorylation of myosin light chain in a cell free system. The rate of phosphorylation has been reported to be affected in an approximately linear manner by static magnetic field strengths in the range 0-200 microT. We performed three series of experiments, two to test the general hypothesis and a third that was a direct replication of published work. We found no effect of static magnetic field strength on the rate of phosphorylation. Hence, we were unable to confirm that weak static magnetic fields affect the binding of calcium to calmodulin. In view of the difficulty we and other authors have had making independent verifications of claimed biological effects of magnetic fields, we would urge caution in the interpretation of published data until they have been independently confirmed. There are still few well defined biological effects of low level magnetic fields that have been successfully transferred to an independent laboratory. Copyright 2000 Wiley-Liss, Inc.