Research Highlights

Novel treatment for hyper-reflexia after spinal cord injury.

Title:  Novel treatment for hyper-reflexia after spinal cord injury.

PI/Investigator:  Charlotte Yates, PT, Ph.D., Project leader; E. Garcia-Rill, COBRE PI.

Institution:  Center for Translational Neuroscience (COBRE), Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, AR

Background:  One of the major, incapacitating symptoms of spinal cord injury (SCI) is hyper-reflexia.  Excessive reflexes and spasms make therapy difficult and delay or prevent recovery.  No effective treatments are available, although in cases with serious spasticity, baclofen, a GABA agonist that makes you sleepy (soporific), is used.  In extreme cases, baclofen pumps are implanted in the spinal canal to attempt to calm excessive reflexes and spasticity.

Advance:  These studies found a novel mechanism may be affected by SCI.  The stimulant modafinil, which is used for the treatment of daytime sleepiness, was found to increase electrical coupling by adding gap junctions, thereby increasing the ability of cells to fire together, that is, with greater coherence.  We found that modafinil completely normalized hyper-reflexia in rats after SCI within 30 days.  These results suggest that a) one of the mechanisms affected by SCI is electrical coupling in the spinal cord, which has not been well studied, and b) this agent may be used to reverse these disturbances.

Support:  Project support and Core Facilities provided by COBRE award P20 GM104325.

Public Health Impact:  This novel treatment may not only alleviate the excessive reflexes induced after SCI, but also replace the soporific effects of the current treatment (baclofen) with the stimulant effects of modafinil.  This strategy may not only more effectively decrease hyper-reflexia, but also increase cognitive function.

Citation and links: 

Yates, C., Charlesworth, A., Reese, N.B., Ishida, K., Skinner, R.D. and Garcia-Rill, E.    Modafinil normalized hyperreflexia after spinal transection in adult rats. Spinal Cord 47:481-485, 2009. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2726738/