Investigation of the effect of 6-week ligation of sciatic nerve on neuropathic pain and dynein gene expression in rats

Axonal transport is a vital process in nervous system. Impairment of motor proteins involved in axonal transport like dynein is a common factor in several neurodegenerative disorders such as amyotrophic lateral sclerosis (ALS). However, no study found on abnormalities in axonal transport due to decreased physical activity and neuropathic pain. Ten adult male Wistar rats (250±30 g) were randomly divided into two groups including healthy control (C) (n=5) and decreased physical activity (SNL) (n=5). Over the six weeks, neuropathic pain behavioral tests conducted continually in groups. At the end of sixth week, change of dynein gene expression in sciatic nerve measured with real time technique and calculated using the 2-ΔΔCT method. 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 that in control group (p<0.05). In addition, dynein gene expression in sciatic nerve ligation group compared to controls significantly decreased (p<0.05). It seems that neuropathic pain and decreased physical activity is associated with decreased dynein gene expression in sciatic nerve fiber. According to the physiologic functions of dynein in neurons, this condition may cause functional disorders in the neural and muscular systems.