People / Graduate Students

Pamela Harvey

A major goal of spinal cord injury research is to restore the pathway of information carried by ascending and descending fibers through the site of injury.  Spinal cord injuries are devastating because most central nervous system axons that are damaged do not regrow to re-establish functional connections, in contrast to the robust regrowth of axons in the periphery.  The presence of both inhibitory molecules and the lack of trophic support in the adult spinal cord have long been recognized as obstacles to regeneration.  Use of various Nogo or Nogo receptor (NgR) antagonists to block myelin-associated inhibition has provided convincing anatomical evidence for regeneration accompanied by positive behavioral recovery.  Additionally, recent evidence from our lab and our collaborators indicate that a member of the GDNF family of neurotrophic factors encourages significant regrowth of axons in the central nervous system.  My project focuses on these treatments individually and in combination using the dorsal root crush paradigm.  I am using neurotracers to label restricted populations of sensory fibers (cutaneous and muscle) and evaluate specificity of regenerated connections in the spinal cord.  I am also using electrophysiological techniques and quantitative behavioral analyses to assess functional synaptogenesis.  These techniques will allow me to determine the relative and/or synergistic efficacies of blocking myelin-associated inhibition and providing positive growth signals, the relative contributions of regeneration and sprouting to recovery, the specificity of regenerated synapses, and the extent to which longer-range connections are re-established.