title: Extensive spontaneous plasticity of corticospinal projections after primate spinal cord injury.
abstract: Although axonal regeneration after CNS injury is limited, partial injury is frequently accompanied by extensive functional recovery. To investigate mechanisms underlying spontaneous recovery after incomplete spinal cord injury, we administered C7 spinal cord hemisections to adult rhesus monkeys and analyzed behavioral, electrophysiological and anatomical adaptations. We found marked spontaneous plasticity of corticospinal projections, with reconstitution of fully 60% of pre-lesion axon density arising from sprouting of spinal cord midline-crossing axons. This extensive anatomical recovery was associated with improvement in coordinated muscle recruitment, hand function and locomotion. These findings identify what may be the most extensive natural recovery of mammalian axonal projections after nervous system injury observed to date, highlighting an important role for primate models in translational disease research.
authors.affiliation: Department of Neurosciences, University of California San Diego, La Jolla, California, USA.
authors.forename: Ephron S
authors.initials: ES
authors.lastname: Rosenzweig
authors.forename: Gregoire
authors.initials: G
authors.lastname: Courtine
authors.forename: Devin L
authors.initials: DL
authors.lastname: Jindrich
authors.forename: John H
authors.initials: JH
authors.lastname: Brock
authors.forename: Adam R
authors.initials: AR
authors.lastname: Ferguson
authors.forename: Sarah C
authors.initials: SC
authors.lastname: Strand
authors.forename: Yvette S
authors.initials: YS
authors.lastname: Nout
authors.forename: Roland R
authors.initials: RR
authors.lastname: Roy
authors.forename: Darren M
authors.initials: DM
authors.lastname: Miller
authors.forename: Michael S
authors.initials: MS
authors.lastname: Beattie
authors.forename: Leif A
authors.initials: LA
authors.lastname: Havton
authors.forename: Jacqueline C
authors.initials: JC
authors.lastname: Bresnahan
authors.forename: V Reggie
authors.initials: VR
authors.lastname: Edgerton
authors.forename: Mark H
authors.initials: MH
authors.lastname: Tuszynski
mesh_terms: D000818:Animals; D004576:Electromyography / Q000379:methods; D005260:Female; D008253:Macaca mulatta; D008297:Male; D009043:Motor Activity / Q000502:physiology; D009473:Neuronal Plasticity / Q000502:physiology*; D011712:Pyramidal Tracts / Q000502:physiology*; D011999:Recruitment, Neurophysiological / Q000502:physiology*; D013119:Spinal Cord Injuries / Q000503:physiopathology*