Abstract

The aim is to investigate the analgesic effect of transcranial direct current stimulation(tDCS) on central neuropathic pain(CNP) in spinal cord contusive rat model. Twenty Sprague-Dawley rats(<TEX>$250{\pm}50$</TEX> g, male) were used. Thoracic spinal cord(T10) was contused using New York University(NYU) spinal cord impactor. The animals were randomly assigned to two groups; GroupI: Non-treatment after SCI induction(n=10), GroupII: application of tDCS(0.1 mA, 20 min/time, 2 times/day, 5 days/6week) after SCI induction(n=10). Assess the effect of tDCS using the Basso Beattie Bresnahan(BBB) locomotor rating scales, Touch <TEX>$test^{TM}$</TEX> sensory evaluator(TTSE), Plantar test<TEX>$^{\circledR}$</TEX>after contusion at the <TEX>$2^{nd}$</TEX>, <TEX>$3^{rd}$</TEX>, <TEX>$4^{th}$</TEX>, <TEX>$5^{th}$</TEX>, <TEX>$6^{th}$</TEX> week and the immunohistochemistric response of c-fos in the thalamus, cerebral cortex after contusion at the <TEX>$3^{rd}$</TEX>, <TEX>$6^{th}$</TEX> week after SCI. The scores of BBB scales were significantly different from <TEX>$3^{rd}$</TEX>week. TTSE were different significantly over time, but there were no differences at each evaluation times on between-measure time effects. Plantar test were different significantly over time and there were difference at the <TEX>$4^{th}$</TEX>, <TEX>$6^{th}$</TEX> week after SCI on between-measure time effects. Also, immunohistochemistric response of c-fos was reduced significantly from <TEX>$3^{rd}$</TEX>, <TEX>$6^{th}$</TEX> week after SCI in tDCS group compared with control group in thalamus and cortex. These results identified that tDCS of non-invasive therapeutic method may have beneficial analgesic effect on CNP after SCI with behavioral test and immunohistochemical test.