A comparison of the effect of mid-thoracic spinal hemisection in the neonatal or weanling rat on the distribution and density of dorsal root axons in the lumbosacral spinal cord of the adult

摘要: Abstract Transecting the thoracic spinal cord of rat has markedley different effects on behavioral responses hindlimbs if lesion is made at neonatal or weanling stage development65,70. The present investigation tested possibility that differences were related to a difference in distribution density dorsal root connections lumbosacral cord. In order use each animal as its own control and axons was compared two sides L5-S1 segments adult rats given mid-thoracic hemisection development. Comparing experimental (initially hemisected side) cord, we found no evidence for change axons. Fink-Heimer stained degeneration 4–6 days after bilateral section virtually identical from animals either stage. However, spinally (n= 8), significantly greater within intermediate nucleus Cajal (INC) side using coded material blind analysis. No detected group 6). Controls indicated increased not due compression resulting shrinkage INC remaining initial hemisection. We conclude amount argyrophilia neonatally an this zone. This result supports hypothesis when comparing transected stages development are number