title: Experimental study of neural repair of the transected spinal cord using peripheral nerve graft.
abstract: It has been reported that transected spinal cord shows signs of axonal regeneration after peripheral nerve (PN) graft. We studied the membrane excitability and ion distribution in axons from transected rat spinal cord 3 weeks after PN graft using the spinal cord evoked potential, electron probe X-ray microanalysis, and the patch-clamp technique. Axonal structures were also observed using conventional electron microscopy. At the Th11 level, laminectomy was performed (=control) and the left thoracic segments of the spinal cord 2 mm in length were excised (=nongrafted group). PN sections from 8-week-old male Wistar rats were grafted into the spinal cord gap (=PN-grafted group). The spinal cord evoked potential in the PN-grafted group partly recovered in contrast to that in the nongrafted group, which showed no recovery. Higher Na, Cl, and Ca peaks and lower K peaks in the PN-grafted group were demonstrated compared with those in the nongrafted group. In the PN-grafted group, a higher current signal appeared in the axonal membrane of the spinal cord, suggesting a greater membrane activity compared with that in the nongrafted group. Unlike the nongrafted group, in which no myelinated axons were found, demyelinated axons that were myelinated by Schwann cells from the grafted peripheral nerve were observed in the PN-grafted group. These findings suggested that Schwann cells from the transplanted PN contributed to the repair of the transected spinal cord.
authors.affiliation: Department of Orthopaedic Surgery, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya 663-8501, Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Fukunaga
authors.forename: Sadao
authors.initials: S
authors.lastname: Sasaki
authors.forename: Tokuhide
authors.initials: T
authors.lastname: Fu
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yokoyama
authors.forename: Iluho
authors.initials: I
authors.lastname: Lee
authors.forename: Ikuko
authors.initials: I
authors.lastname: Nakagaki
authors.forename: Seiki
authors.initials: S
authors.lastname: Hori
authors.forename: Hiroomi
authors.initials: H
authors.lastname: Tateishi
authors.forename: Souji
authors.initials: S
authors.lastname: Maruo
mesh_terms: D000818:Animals; D001369:Axons / Q000473:pathology / Q000502:physiology*; D004577:Electron Probe Microanalysis; D005071:Evoked Potentials / Q000502:physiology; D008297:Male; D009416:Nerve Regeneration / Q000502:physiology*; D018408:Patch-Clamp Techniques; D051381:Rats; D017208:Rats, Wistar; D012584:Sciatic Nerve / Q000637:transplantation*; D013116:Spinal Cord / Q000473:pathology / Q000503:physiopathology* / Q000601:surgery*