The Behavioral and Biochemical Effect of Pulsating Magnetic Field Treatment (PMFT) on Chronic Pain Produced by Chronic Constriction Injury of Sciatic Nerve in Rat

Extremely low frequency magnetic fields can either increase or decrease analgaesia in the land snail depending on field and light conditions

“…The results of the present study with the snail Cepaea show that ELF magnetic ®elds either reduce, have no effect, or potentiate/induce opioid-mediated`a nalgaesia'', in a manner consistent with the parametric resonance model (PRM). These ®ndings agree with, and extend, prior ®ndings that opioid-mediated responses are sensitive to magnetic ®elds [Kavaliers and Ossenkopp 1986, 1991Betancur et al, 1994;Kavaliers et al, 1994;Del Seppia et al, 1995;Papi et al, 1995;Parris et al, 1994;Prato et al, 1995Prato et al, , 1996aSeaman et al, 1996;Thomas et al, 1997aThomas et al, , b, 1998]. The present results con®rm the utility of a PRM for addressing various aspects of the biological effects Fig.…”

“…We have more recently shown [Thomas et al, 1997a[Thomas et al, , b, 1998] that exposure of snails to a frequency-modulated pulsed magnetic ®eld can both increase SCH-induced analgaesia and induce analgaesia. At least two other groups have reported increases in anti-nociception (analgaesia) in mice [Seaman et al, 1996] and rats [Parris et al, 1994] exposed to pulsed magnetic ®elds. This report is one of the few [Ross, 1990] which shows that ELF magnetic ®eld exposure can have variable effects on a biological system depending on exposure parameters.…”

Advances in Electromagnetic Fields in Living Systems

“…This is the first time, using a single simple sinusoidal exposure, that we have been able to increase druginduced analgesia and, more importantly, induce analgesia in drug-naive animals. Note that Parris et al, [1994] showed that repeated simple sinusoidal ELF magnetic field exposures could increase analgesia in rats and Kavaliers and Ossenkopp [1993] have shown similar results in snails. In summary, we have been able to use the predictions of the PRM to define the ELFMF that would increase analgesia.…”

Alternative Pain Medicine

“…To determine the efficacy if magnetic fields, Parris and coauthors 30 investigated the chronic pain animal model (rat) using the sciatic nerve ligation or chronic construction injury. The objective was to determine whether repeated pulsating magnetic field therapy (PMFT) would affect hyperalgesia and spinal cord, brain, and plasma levels of substance P met‐enkephalin and dynorphin after chronic constriction injury of the rat sciatic nerve.…”