Effect of glial cell line-derived neurotrophic factor on Fos protein expression in the spinal dorsal horn of neuropathic pain rat model

Abstract

Objective To study the effect of glial cell line-derived neurotrophic factor (GDNF)on Fos protein expression in the spinal dorsal horn of neuropathic pain rat model.Methods Adult Sprague-Dawley male rats were randomly divided into normal control group,sham operation group,spinal nerve ligation (SNL) group and SNL combined with treatment of GDNF group.Every group was divided into three sub-groups:SNL 3,7 and 14 days (n =10 in each group).Fos protein expression in the spinal dorsal horn was examined by using inununohistochemistry and Western blotting.Results Compared with normal control and sham operation groups,the Fos protein expression in the spinal dorsal horn of the rats in SNL group was increased significantly (1.00 ± 0.00,1.08 ± 0.12,and 4.62 ± 0.52 respectively).As compared with the rats in SNL group,there was an apparent decrease in GDNF treatment group three days later (1.82 ± 0.51).Conclusion Fos protein in the spinal dorsal horn of rats was involved in the mechanism of neuropathic pain.Intrathecal administration of GDNF could inhibit Fos protein expression in the spinal dorsal horn. Key words: Glial cell line-derived neurotrophic factor; Neuropathic pain; Fos protein