Regeneration of dorsal column axons after spinal cord injury in young rats.
In contrast to previous reports denying the occurrence of axonal regeneration of the dorsal column (DC) projections, here we demonstrate for the first time that marked regeneration occurs spontaneously after transection in infant rats. Transection was made sharply so as to produce edema-free lesions without subsequent formation of either scars or cysts. Transganglionic labeling of axons revealed that regenerated axons ascended in the normal tract in a manner similar to normal projections as a tightly-packed fasciculus and terminated densely in the nucleus gracilis. The present study indicates that failure of regeneration of DC axons is due to neither intrinsic deficiency of regrowth potential nor globally-inhospitable axonal environment but rather the local conditions of the lesion site.
Kikukawa
S
S
Department of Integrative Brain Science, Kyoto University Graduate School of Medicine and Faculty of Medicine, Japan.
Kawaguchi
S
S
Mizoguchi
A
A
Ide
C
C
Koshinaga
M
M
D000818:Animals; D000831:Animals, Newborn; D019771:Axotomy; D002772:Cholera Toxin; D006735:Horseradish Peroxidase; D018613:Microscopy, Confocal; D015335:Molecular Probes; D009416:Nerve Regeneration / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D013116:Spinal Cord / Q000033:anatomy & histology / Q000473:pathology / Q000502:physiology*; D013119:Spinal Cord Injuries / Q000503:physiopathology*; D018998:Wheat Germ Agglutinin-Horseradish Peroxidase Conjugate
D015335:Molecular Probes; D018998:Wheat Germ Agglutinin-Horseradish Peroxidase Conjugate; C052635:cholera toxin, B subunit-horseradish peroxidase; D002772:Cholera Toxin; D006735:Horseradish Peroxidase