Expression of nuclearfactor kappa B and neuropathic pain

：Objective To investigatethe expression of nuclear factor kappa B(NF-κB)in the lumbar spinal cord in chronic constrictive injury(CCI)ofthe sciatic nerve.Methods Foay-eight male Sprague-Dawley rats were divided into 2groups(n=24 in each).The operation group received CCI of the sciatic nerve and thesham-operation group received a sham operation as a control.Their mechanical and thermalnociceptive thresholds were assessed with paw withdrawal latency (PWL) using von Freyfilaments and radiant heating.Four rats were sacrificed at each time point and segments oftheir lumbar spinal cords were examined using Western blotting.Results Mechanical andthermal stimulation thresholds were reduced significantly after the operation.Expressionof NF-κB protein increased significantly inthe ipsilateral dorsal horn of the spine compared with the contralateral side and comparedwith the sham-operation group.NF-κB proteinexpression began to increase on the 1 st day after the operation,reached a peak at the 7thday,and stayed high throughout the experiment.Conclusion NF-κB in the dorsal horn of the spine may be involved in neuropathiepain after CCI.