Effects of Valproic Acid on Axonal Regeneration and Recovery of Motor Function after Peripheral Nerve Injury in the Rat

Document Type : RESEARCH PAPER


1 Department of Urology People Hospital of Wuhan University, Wuhan City Hu Bei Province, People’s Republic of China

2 Department of Hand surgery and Microsurgery Pu Ai Hospital of Huazhong University of Science and Technology, Wuhan City, Hu Bei Province People’s Republic of China


Valproic acid (VPA) is used to be an effective anti-epileptic drug and mood stabilizer. It has recently
been demonstrated that VPA could promote neurite outgrowth, activate the extracellular signal regulated kinase pathway,
and increases bcl-2 and growth cone-associated protein 43 levels in spinal cord. In the present research we
demonstrate the effect of VPA on peripheral nerve regeneration and recovery of motor function following sciatic nerve
transaction in rats.
The rats in VPA group and control group were administered with valproic acid (300mg/kg) and sodium
chloride respectively after operation. Each animal was observed sciatic nerve index (SFI) at 2-week intervals and
studied electrophysiology at 4-week intervals for 12 weeks. Histological and morphometrical analyses were performed
12 weeks after operation. Using the digital image-analysis system, thickness of the myelin sheath was measured, and
total numbers of regenerated axons were counted.
There was a significant difference in SFI, electrophysiological index (motor-nerve conduct velocity), and
morphometrical results (regenerated axon number and thickness of myelin sheath) in nerve regeneration between the
VPA group and controls (
The results demonstrated that VPA is able to enhance sciatic nerve regeneration in rats, suggesting
the potential clinical application of VPA for the treatment of peripheral nerve injury in humans.


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  • Receive Date: 02 January 2014
  • Revise Date: 01 February 2014
  • Accept Date: 22 February 2014
  • First Publish Date: 01 March 2014