P-104 - (Poster #104) Histological Findings After Electromagnetic Field Stimulation in a Sciatic Nerve Constriction Model in Rats for Neuropathic Pain

Background: Neuropathic pain is a type of pain that occurs due to injury to the nervous system. Stimulation of the nervous system with magnetic fields can be used with non-invasive interventions. Low-Frequency EMFs produce neurite growth in Chromaffin Cells and activate Nerve Growth Factor. This data proposes that neuropathic pain can be diminished by using EMFs in the nervous system. An animal model should be addressed to obtain in vivo data using histological studies.

Purpose/Objectives:

Purpose: Evaluate histological findings after using EMF in a Sciatic Nerve Constriction model used to create Neuropathic Pain.

Methods:

Methods: SNC was done to cause neuropathic pain in the right hind limb in male Sprague-Dawley rats (380g-520g). Three groups of (n=10) rats were created. Control Group (CG) was just injured. The experimental groups were EMF-treated two hours a day for four weeks (2/24, 5/7, 4/4), applying Gauss intensities: Low-Intensity (LIMF) 60-100 (6-10 mT) & High-Intensity (HIMF) 140-200 (14-20 mT). Sciatic nerve and skeletal muscle histological slides were made with traditional obtention and staining techniques to evaluate cellular inflammation. Slides obtained were qualitative analyzed contrasting groups with sciatic nerve and skeletal muscle tissue, identifying inflammatory leukocyte lines. For analyzing images, we utilized a simple optical microscope.

Results:

Results: Histological findings were the following: CG had hypercellular Schwann cells. LIMF formed calcifications with perimysium and endomysium fibrosis. In HIMF thinning of the sciatic nerve was observed, and skeletal muscle had moderate atrophy with adipose infiltration. EMFs in LIMF & HIMF effective in diminishing inflammation cells in sciatic nerve & skeletal muscle in contrast with CG. Sciatic Nerve in EMF groups decresed cell inflammation, and cytoarchitecture was reestablished to normality.

Conclusions/Implications for future research and/or clinical care:

Conclusions: Upcoming research should be done to detail molecular and cellular mechanisms of neuropathic pain, to clarify the phenomena. Histological images strengthen theories of nerve regeneration after the use of EMFs after sciatic nerve constriction, showing that CG had nerve and muscle inflammation, but LIMF & HIMF diminished immunological cellular activity due to the inflammation process. Studies should aim to understand molecular pathways involved in nerve regeneration.  This model makes an outstanding contribution to clarify EMFs effects in neuropathic pain histology.