Pretreatment of rats with pulsed electromagnetic fields enhances regeneration of the sciatic nerve.
Regeneration of the sciatic nerve was studied in rats pretreated in a pulsed electromagnetic field (PEMF). The rats were exposed between a pair of Helmholtz coils at a pulse repetition rate of 2 pps at a field density of 60 or 300 microT. The PEMF treatment was then discontinued. After an interval of recovery, regeneration of the sciatic nerve was initiated by a crush lesion. Regeneration of sensory fibers was measured by the "pinch test" after an additional 3-6 days. A variety of PEMF pretreatments including 4 h/day for 1-4 days or exposure for 15 min/day during 2 days resulted in an increased regeneration distance, measured 3 days after the crush lesion. This effect could be demonstrated even after a 14-day recovery period. In contrast, pretreatment for 4 h/day for 2 days at 60 microT did not affect the regeneration distance. The results showed that PEMF pretreatment conditioned the rat sciatic nerve in a manner similar to that which occurs after a crush lesion, which indicates that PEMF affects the neuronal cell body. However, the mechanism of this effect remains obscure.
Kanje
M
M
Department of Animal Physiology, University of Lund, Sweden.
Rusovan
A
A
Sisken
B
B
Lundborg
G
G
D000818:Animals; D004599:Electric Stimulation Therapy / Q000379:methods*; D004574:Electromagnetic Fields; D005260:Female; D009416:Nerve Regeneration / Q000528:radiation effects*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012584:Sciatic Nerve / Q000293:injuries / Q000502:physiology* / Q000528:radiation effects*; D013997:Time Factors