In studying the responses of neuron cells to applied static magnetic fields (SMF) we have been able to separate two neuron populations: sensu stricto magnetosensitive neurons, or fast-SMF-response neurons, whose electrophysiological activity is modified through a Ca2+ - dependent ionic mechanism and slow-SMF-response neurons whose electrophysiological activity is mediated by non-specific mechanisms. SMF mobilizes Ca2+ ions from the ones bound to the plasma membrane increasing as a result the [Ca2+]i. The increase in [Ca2+]i either operates on the Ca2+-dependent-K+- channels or depolarizes the membrane resulting in the inhibition or excitation of the neuron activity. The ionic mechanism underlying inhibition and excitation under SMF is unique: the increase of free cytosolic [Ca2+]. In considering that cellular magnetosensitivity could be based on the induced reorientation of membrane phospholipid bilayer under applied SMF, magnetosensitivity must be a quite general membranes property.
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