RESUMEN
ObjectiveTo explore the projections of the long descending propriospinal tracts to lumbar enlargement. Method Anterograde tracing with cupric-silver staining. 10 animals were injected b biotinylated dextran in the upper cervical cord. Following survival times of 14 days, projections of the long descending propriospinal tracts were immunohistochemically demonstrated in the lumbar enlargement.Results The degenerated terminals and labeled terminals were found in the bilateral gray matter of the lumbar enlargement, but predominantly ipsilaterally. The terminals were widely distributed in laminal Ⅴ-Ⅸ, heavily Ⅶ and Ⅷ. Conclusion The long descending propriospinal tract from the upper cervical cord projects to the lumbar enlargement.
RESUMEN
The direct spinal projections from the cerebellar nuclei in the rabbit were retro gradely traced by unilateral injection of WGA-HRP into different levels of the spinal cord, including the cervical, thoracic and lumbar segments. The labeled neurons in the cerebellar nuclei were constantly seen in those animals, in which the upper cervical segments (C_(2-4)) were injected. No labeled neurons could be found in the cerebellar nuclei following injection into the lower cervical cord (C_(6-8)) or more caudal segments. All labeled neurons were located in the caudal parts of the fastigial and the interposed nuclei on the side contralateral to the injection. The results show that there are crossed projections from the cerebellar nuclei directly to the upper cervical cord. This study provide certain morphological evidences for further investigation of some aspects of cerebellar functions on motor coordination.