Spatiotemporal Pattern of Concurrent Spinal and Supraspinal NF-κB Expression After Peripheral Nerve Injury

• Published in: The journal of pain Vol. 12; no. 1; pp. 13 - 21
• Main Authors: Chou, Chiu-Wen, Wong, Gordon T.C, Lim, Grewo, Wang, Shuxing, Irwin, Michael G, Mao, Jianren
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 2011
• Subjects: affective; amygdala; Anesthesia & Perioperative Care; Animals; anterior cingulate cortex; Disease Models, Animal; Dizocilpine Maleate - pharmacology; Dizocilpine Maleate - therapeutic use; Functional Laterality - physiology; Gene Expression Regulation - drug effects; Gene Expression Regulation - physiology; Male; Neuralgia - drug therapy; Neuralgia - etiology; Neuralgia - metabolism; Neuropathic pain; Neuroprotective Agents - pharmacology; Neuroprotective Agents - therapeutic use; NF-kappa B - metabolism; NF-κB; Pain Measurement; Pain Medicine; Peripheral Nervous System Diseases - complications; Peripheral Nervous System Diseases - metabolism; Peripheral Nervous System Diseases - pathology; Rats; somatosensory cortex; Somatosensory Cortex - metabolism; Spinal Cord - metabolism; Synaptotagmin I - metabolism; thalamus; Thalamus - metabolism; Thalamus - pathology; NF-κB; amygdala; affective; somatosensory cortex; anterior cingulate cortex; Neuropathic pain; thalamus
• ISSN: 1526-5900; 1528-8447
• DOI: 10.1016/j.jpain.2010.03.018

Abstract The expression of NF-κB in the spinal cord is associated with neuropathic pain. However, little is known about its expression beyond the spinal cord. Here we examined a spatial and temporal pattern of the NF-κB expression in both spinal and supraspinal regions. After chronic constriction injury (CCI) of the sciatic nerve, NF-κB (p65) expression was significantly increased in the ipsilateral spinal cord. In contrast, the NF-κB expression in the contralateral primary somatosensory cortex was decreased with no significant differences seen in the thalamus. In the contralateral anterior cingulate cortex, the NF-κB expression was increased significantly on day 14 as compared with the sham group. In the contralateral amygdala, the NF-κB expression showed a time-dependent downregulation after CCI, which became significant on day 14. MK-801 reduced nociceptive behaviors and reversed the direction of NF-κB expression. These results indicate that the CCI-induced expression of p65 NF-κB is both time-dependent and region-specific, in areas that process both sensory-discriminative and motivational-affective dimensions of pain. Perspective This article presents a spatiotemporal mapping of the NF-κB expression in spinal and supraspinal regions after peripheral nerve injury. These findings point to an involvement of NF-κB beyond the spinal cord in both the sensory discriminative and emotional affective aspects of neuropathic pain processing.