Acute exposure to high-induction electromagnetic field affects activity of model peripheral sensory neurons

Exposure to repetitive low-frequency electromagnetic field (LF-EMF) shows promise as a non-invasive approach to treat various sensory and neurological disorders. Despite considerable progress in the development of modern stimulation devices, there is a limited understanding of the mechanisms underlying their biological effects and potential targets at the cellular level. A significant impact of electromagnetic field on voltage-gated calcium channels and downstream signalling pathways has been convincingly demonstrated in many distinct cell types. However, evidence for clear effects on primary sensory neurons that particularly may be responsible for the analgesic actions of LF-EMF is still lacking. Here, we used F11 cells derived from dorsal root ganglia neurons as an in vitro model of peripheral sensory neurons and three different protocols of high-induction magnetic stimulation to determine the effects on chemical responsiveness and spontaneous activity. We show that short-term (<180 sec.) exposure of F11 cells to LF-EMF reduces calcium transients in response to bradykinin, a potent pain-producing inflammatory agent formed at sites of injury. Moreover, we characterize an immediate and reversible potentiating effect of LF-EMF on neuronal spontaneous activity. Our results provide new evidence that electromagnetic field may directly modulate the activity of sensory neurons and highlight the potential of sensory neuron-derived cell line as a tool for studying the underlying mechanisms at the cellular and molecular level.