Iranian Journal of

Background: Neuropathic pain is associated with a profound impact on quality of life and daily activity in patients and caused high medical costs. Because of the nerves destructive nature in this disease, the neurotrophins are high regarded for their possible effects on survival, growth and development and neuronal functions as a possible therapeutic strategy. So the aim of this study is investigation of the chronic effects of decreased activity in neuropathic pain form on the NFG gene expression in the sciatic nerve of Spinal nerve ligated rats.

Methods: Ten adult male Wistar rats in the weight range of 250±30 gr randomly were divided into two groups including healthy control (C), ligation sciatic nerve ligation. Over the six weeks neuropathic pain behavior tests were conducted continually in groups. In the end change of NGF gene expression in sciatic nerve was measured with Real time PCR technique and calculated using the ^{2-&Delta&DeltaCT} method.

Results: After 6 weeks, neuropathic pain behavior tests showed that pain threshold of thermal hyperalgesia and mechanical allodynia in the SNL group was significantly lower than the control group (P&le0.05). In addition, NGF gene expression in sciatic nerve ligation group compared to controls increased significantly (P&le0.05).

Conclusion: The findings of this study suggest that the development of neuropathic pain and decreased physical activity is associated with increased endogenous NGF. Although it is not clear that increase in NGF expression is due to the nature of neuropathic pain or nerve damage, it is clear that excessive expression of NGF is associated with neuropathic pain.