Role of NF-κB in astrocytes in spinal dorsal horn in a rat model of neuropathic pain induced by paclitaxel

Objective To evaluate the role of NF-κB in astrocytes in the spinal dorsal horn in a rat model of neuropathic pain induced by paclitaxel.Methods Twenty 6 year old male SD rats weighing 180-200 g were randomly divided into 2 groups ( n =10):control group (group C) and neuropathic pain group (group NP).Neuropathic pain was induced by intraperitoneal injection paclitaxel of 2 mg/kg every other day for 4 times in group NP.While the equal volume of normal saline was given instead of paclitaxel in group C.Body weight,mechanical pain threshold and heat pain threshold were determined before and at 1,7,14 d after administration.The animals were sacrificed and the spinal dorsal horn were removed for determination of NF-κB p65 expression in astrecytes by immunofluorescence analysis at 14 d after administration.Results There was no significant difference in body weight between the two groups( P ＞ 0.05).Compared with group C,mechanical pain threshold and heat pain threshold were significantly decreased 7 and 14 d after administration,the expression of NF-κB p65 in astrocytes in the spinal dorsal horn was up-regulated in group NP( P ＜ 0.05 or 0.01 ).Conclusion Activation of NF-κB in astrocytes in the spinal dorsal horn may play an important role in neuropathic pain induced by paclitaxel in rats. Key words: NF-κB;  Astrocytes;  Spinal cord;  Paclitaxel;  Neuralgia