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An electron microscopic analysis of abnormal ependymal cell proliferation and envelopment of sprouting axons following spinal cord transection in the rat

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Summary

Transection of the spinal cord in a series of Long Evans hooded rats results in a rapid degeneration of elements of the neuropil and white matter adjacent to the lesion site, and in the appearance of a wide variety of reactive cellular elements which ingest necrotic debris and produce a connective tissue matrix in the defect left by the lesion. Included among the non-neuronal elements found within the lesion zone and adjacent spinal cord segments cranial to the lesion were large clusters of ependymal cells displaced from their normal location. This aberrant proliferation produces extensive cords and nests of ependymal cells some of which maintain contiguity with those elements lining the central canal while other clusters were found several 100 μm distant in the gray matter. Rosettes with distinct lumina often occurred in such cellular aggregates and were similar in arrangement to those patterns displayed by primitive neuroepithelial cells following experimental manipulation (Watterson, 1965). Electron microscopy revealed typical oval euchromatin nuclei with a pale cytoplasm containing concentrations of filaments. Examination of rosette lumina revealed normal apical specializations including cilia with basal bodies, microvilli, and numerous zonulae adherentes Intracytoplasmic vacuole formation with abnormal microvilli and cilia were reminiscent of patterns described in certain ependymomas (Fu et al., 1974).

During the period between 15–45 days following injury, axons sprout into the scar matrix and along the adjacent, eroded cord segments. Those fibers which became apposed to the aberrant ependymal cells were enveloped by them and a typical “mesaxon” was formed. With increasing postoperative periods until 90 dpo, groups of 3–8 fibers could be found enclosed within a single cell.

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References

  • Azzarelli, B., Rekate, H. L., Roessmann, U.: Subependymoma: A case report with ultrastructural study. Acta. Neuropathol. (Berl.)40, 279–282 (1977)

    Google Scholar 

  • Betty, M. J.: Ependymal hyperplasia in the lateral ventricle of the guinea pig. J. Comp. Pathol.87, 185–194 (1977)

    Google Scholar 

  • Bryant, S. V., Wozny, K. J.: Stimulation of limb regeneration in the lizard Xantusia vigilis by means of ependymal implants. J. Exp. Zool.189, 399–352 (1974)

    Google Scholar 

  • Egar, M., Singer, M.: The role of ependyma in spinal cord regeneration in the urodele, Triturus. Exp. Neurol.37, 422–430 (1972)

    Google Scholar 

  • Escolá-Pico, J.: Die Feinstruktur versenkter Ependymzellen innerhalb von gliösen Narbenbereichen. Acta Neuropathol. (Berl.)3, 137–143 (1963)

    Google Scholar 

  • Feringa, E. R., Shuer, L. M., Vahlsing, H. L., Davis, S. W.: Regeneration of corticospinal axons in the rat. Ann. Neurol.2, 315–321 (1977)

    Google Scholar 

  • Fu, Y., Chen, A. T. L., Kay, S., Young, H. F.: Is subependymoma (Subependymal glomerate astrocytoma) an astrocytoma or ependymoma? Cancer34, 1992–2008 (1974)

    Google Scholar 

  • Gamble, H. J.: Axon ensheathing by ependymal cells in the human embryonic and foetal spinal cord. Nature218, 182–183 (1968)

    Google Scholar 

  • Jungherr, E. L., Gabasso, V. J., Stebbin, M.: Comparative pathology of attenuated polio and simian viruses 12 and 40. J. Neuropathol. Exp. Neurol.22, 512–527 (1963)

    Google Scholar 

  • Luse, S. A.: Ultrastructural characteristics of normal and neoplastic cells. Prog. Exp. Tumor Res.2, 1–35 (1961)

    Google Scholar 

  • Matinian, L. A., Andreasian, A. S.: Enzyme therapy in organic lesions of the spinal cord. Brain Information Service, UCLA 1976

  • Matthews, M. A., St. Onge, M. F., Faciane, C. L.: Abnormal proliferation of ependymal cells following spinal cord injury. Anat. Rec.190, 472–473 (1978)

    Google Scholar 

  • Matthews, M. A., St. Onge, M. F., Faciane, C. L., Gelderd, J. B.: Spinal cord transection: A quantitative analysis of elements of the connective tissue matrix formed within the site of lesion following administration of Piromen, Cytoxan or Trypsin. Neuropath. Appl. Neurobiol. (in press, 1978a)

  • Matthews, M. A., St. Onge, M. F., Faciane, C. L., Gelderd, J. B.: Axon sprouting into segments of rat spinal cord adjacent to the site of a previous transection. Neuropath. Appl. Neurobiol. (in press, 1978b)

  • Nordlander, R. H., Singer, M.: The role of ependyma in regeneration of the spinal cord in the urodele amphibian tail. J. Comp. Neurol.180, 349–374 (1978)

    Google Scholar 

  • Ogata, J., Hochwald, G. M., Cravioto, H., Ransohoff, J.: Light and electron microscopic studies of experimental hydrocephalus. Ependymal and subependymal areas. Acta Neuropathol. (Berl.)21, 213–223 (1972)

    Google Scholar 

  • Privat, A., Leblond, C. P.: The subependymal layer and neighboring region in the brain of the young rat. J. Comp. Neurol.146, 277–302 (1972)

    Google Scholar 

  • Shellshear, I., Emery, J. L.: Gliosis and aqueductule formation in the aqueduct of Silvius. Dev. Med. Child. Neurol.. [Suppl.]37, 22–28 (1976)

    Google Scholar 

  • Simpson, S. B.: Morphology of the regenerated spinal cord in the lizard, Anolis carolinensis. J. Comp. Neurol.134, 193–210 (1968)

    Google Scholar 

  • Smart, I. H. M.: Proliferative characteristics of the ependymal layer during the early development of the spinal cord in the mouse. J. Anat.111, 365–380 (1972)

    Google Scholar 

  • Vick, N. A., Lin, M., Bigner, D. D.: The role of the subependymal plate in tumorigenesis. Acta Neuropathol. (Berl.)40, 63–71 (1977)

    Google Scholar 

  • Watterson, R.: Structure and mitotic behavior of the early neural tube. In: Organogenesis. Eds. R. L. DeHaan and H. Ursprung. Chapter 5. New York: Holt, Rinehart and Winston 1965

    Google Scholar 

  • Weller, R. O., Wisniewski, H., Shulman, K., Terry, R. D.: Experimental hydrocephalus in young dogs: Histological and ultrastructural study of the brain tissue damage. J. Neuropathol. Exp. Neurol.30, 613–626 (1971)

    Google Scholar 

  • Wisoff, H. S., Ghatak, N. R.: Ependymal cyst of the spinal cord: Case report. J. Neurol. Neurosurg. Psychiatry34, 546–550 (1971)

    Google Scholar 

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Matthews, M.A., St. Onge, M.F. & Faciane, C.L. An electron microscopic analysis of abnormal ependymal cell proliferation and envelopment of sprouting axons following spinal cord transection in the rat. Acta Neuropathol 45, 27–36 (1979). https://doi.org/10.1007/BF00691801

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