Changes of IL-6 protein levels in the rat dorsal root ganglia of two experimental models of neuropathic pain.
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| Year of publication | 2008 |
| Type | Conference abstract |
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| Description | Cytokines play a role in the induction and maintenance of neuropathic pain. IL-6 is pro-inflammatory cytokine involved in various processes of nervous system including neuronal differentiation, neuroprotection, and neuronal degeneration. Two rat experimental models of neuropathic pain were used for investigation of temporal changes of IL-6 protein levels in both ipsi- and contralateral lumbal (L4-L5) and cervical (C6-C7) dorsal root ganglia (DRG) and plasma. Rats of first experimental model were operated aseptically on triple unilateral ligation of sciatic nerve (ScNL); rats of second experimental model were operated on ligature of L4-L5 spinal nerves (SNL). The animals were divided into three groups: naive group (rat without any operation, n=6); operated group (n=24) with periods of survival for 1, 3, 7 and 14 days; sham operated group (operated rats without nerve lesion, n=12) with periods of survival 3 and 14 days. Commercially available ELISA test (BioSource, CA, USA) was used for quantitative analysis of IL-6 protein. One day after ScNL, significantly increased levels of IL-6 protein were observed in both ipsilateral and contralateral cervical and lumbal DRG. The other periods of survival displayed just mild increase of IL-6 protein levels close to the control (naive group) baseline level. Levels of IL-6 protein were significantly increased from post-operation day 1, and rose up to 14 days from SNL operation not only in ipsi- and contralateral L4-L5 DRG, but also in ipsi- and contralateral C6-C7 DRG. In general, elevation of IL-6 protein was greater in lumbal than cervical DRG. Plasma levels of IL-6 protein measured in both models were significantly lower than in DRG tissue and displayed principally the similar pattern. The obtained data provide evidence for changes of IL-6 protein levels not only in the DRG associated with damaged nerve, but also in those non-associated with nerve injury in two rat experimental neuropathic pain models. Stimuli for bilateral increase of IL-6 protein in the DRG after unilateral nervous lesion are probably of systemic character. |