Behavioral recovery and spinal motoneuron remodeling after polyethylene glycol fusion repair of singly cut and ablated sciatic nerves

Autoři: Cameron L. Ghergherehchi aff001;  Emily A. Hibbard aff002;  Michelle Mikesh aff003;  George D. Bittner aff003;  Dale R. Sengelaub aff002
Působiště autorů: Department of Molecular Biosciences, University of Texas at Austin, Austin, Texas, United States of America aff001;  Department of Psychological and Brain Sciences, Indiana University, Bloomington, Indiana, United States of America aff002;  Department of Neuroscience, University of Texas at Austin, Austin, Texas, United States of America aff003
Vyšlo v časopise: PLoS ONE 14(10)
Kategorie: Research Article


Polyethylene glycol repair (PEG-fusion) of severed sciatic axons restores their axoplasmic and membrane continuity, prevents Wallerian degeneration, maintains muscle fiber innervation, and greatly improves recovery of voluntary behaviors. We examined alterations in spinal connectivity and motoneuron dendritic morphology as one potential mechanism for improved behavioral function after PEG-fusion. At 2–112 days after a single-cut or allograft PEG-fusion repair of transected or ablated sciatic nerves, the number, size, location, and morphology of motoneurons projecting to the tibialis anterior muscle were assessed by retrograde labeling. For both lesion types, labeled motoneurons were found in the appropriate original spinal segment, but also in inappropriate segments, indicating mis-pairings of proximal-distal segments of PEG-fused motor axons. Although the number and somal size of motoneurons was unaffected, dendritic distributions were altered, indicating that PEG-fusion preserves spinal motoneurons but reorganizes their connectivity. This spinal reorganization may contribute to the remarkable behavioral recovery seen after PEG-fusion repair.

Klíčová slova:

Nerve fibers – Nerves – Neuronal dendrites – Soleus muscles – Axons – Sciatic nerves – Muscle fibers – Muscle electrophysiology


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