The possible nitric oxide (NO) system associated with the hyperalgesic effects of the exposure of extremely low frequency magnetic fields was considered. The involvement of calcium-dependent NO pathway in hyperalgesia was evaluated by blocking Ca2+ sources with NMDA receptor antagonist (MK-801) and calcium channel blocker (nimodipine).
|Exposure duration||continuous for 48 h|
The exposure of animals to extremely low frequency magnetic field lowered pain threshold and elevated NO synthesis in brain and spinal cord.The hyperalgesic effects of extremely low frequency magnetic field were shown to be associated with calcium-dependent nitric oxide synthase.The expression of calcium-dependent constitutive nitric oxide synthases and calcium-independent inducibel nitric oxide synthases were not changed by extremely low frequency magnetic fields.
The authors suggest that extremely low frequency magnetic field produce hyperalgesia by modulating NO synthesis via Ca2+-dependent nitric oxide synthase.