NF-κB, ERK, p38 MAPK and JNK contribute to the initiation and/or maintenance of mechanical allodynia induced by tumor necrosis factor-alpha in the red nucleus.

NF-κB, ERK, p38 MAPK and JNK contribute to the initiation and/or maintenance of mechanical allodynia induced by tumor necrosis factor-alpha in the red nucleus. Brain Res Bull. 2013 Oct 23; Authors: Zhang Q, Wang J, Duan MT, Han SP, Zeng XY, Wang JY Abstract Previous studies have demonstrated that tumor necrosis factor-alpha (TNF-α) in the red nucleus (RN) plays facilitated roles in the development of abnormal pain. Here, the roles of nuclear factor-kappa B (NF-κB), extracellular signal-regulated kinase (ERK), p38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinase (JNK) in TNF-α-evoked mechanical allodynia were investigated. Repeated microinjection of recombinant rat TNF-α (20ng daily for 3 days) into the unilateral RN of normal rats induced a significant mechanical allodynia in the contralateral but not ipsilateral hind paw at the fifth day and disappeared 24h later. Re-injection of a single bolus of 20ng TNF-α into the same RN reproduced this mechanical allodynia within 30min, which was used as a pain model for further experiments. Immunohistochemistry demonstrated that NF-κB, phospho-ERK (p-ERK) and p-p38 MAPK in the RN were significantly up-regulated at 1h after TNF-α microinjection, the up-regulations of NF-κB and p-ERK but not p-p38 MAPK remained at high levels till 4h later. A significant up-regulation of p-JNK occurred at 4h (but not 1h) after TNF-α microinjection, which was later than those of NF-κB, p-ERK a...
Source: Brain Research Bulletin - Category: Neurology Authors: Tags: Brain Res Bull Source Type: research