Abstract
Retinal ganglion cells of adult cats have the potential to regenerate their axons into autografted peripheral nerve. Two months after transplantation of the sciatic nerve to the axotomized optic stump, regenerated axons were labeled anterogradely with biocytin, and myelin formation by Schwann cells was examined electron microscopically. Both myelinated and unmyelinated fibers were labeled with biocytin. Among 511 axons labeled in three grafts, 96 fibers (18.8%) were myelinated and 415 (81.2%) were unmyelinated. Mean diameter with SD of myelinated fibers was 1.28 ± 0.39 μm (range 0.71–2.47) and that of unmyelinated fibers was 0.76± 0.38 μm (range 0.18–2.46). The ratio of inner to outer diameters of the myelin sheath (g value) was 0.82, which is close to the value (0.8) for the optic fibers of intact adult cats.
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Bähr M, Eschweiler GW, Wolburg H (1992) Precrushed sciatic nerve grafts enhance the survival and axonal regrowth of retinal ganglion cells in adult rats. Exp Neurol 116:13–22
Bray GM, Villegas-Pérez MP, Vidal-Sanz M, Carter DA, Aguayo AJ (1991) Neuronal and nonneuronal influences on retinal ganglion cell survival, axonal regrowth, and connectivity after axotomy. Ann NY Acad Sci 633:214–228
Campbell G, Lieberman AR, Anderson PN, Turmaine M (1992) Regeneration of adult rat CNS axons into peripheral nerve autografts: ultrastructural studies of the early stages of axonal sprouting and regenerative axonal growth. J Neurocytol 21:755–787
Fukuda Y, Sasaki H, Adachi A, Inoue T, Morigiwa T (1990) Optic nerve regeneration by peripheral nerve transplant. Neurosci Res 13: S24-S30
Horikawa K, Armstrong WE (1988) A versatile means of intracellular labeling: injection of biocytin and its detection with avidin conjugates. J Neurosci Methods 25:1–11
Hsiao CF, Watanabe M, Fukuda Y (1984) The relation between axon diameter and axonal conduction velocity of Y, X and W cells in the cat retina. Brain Res 309:357–361
Izzo PN (1991) A note on the use of biocytin in anterograde tracing studies in the central nervous system: application at both light and electron microscopic level. J Neurosci Methods 36:155–166
Peters A, Palay SL, Webster Hde F (1991) The fine structure of the nervous system. Oxford University Press, New York, pp 262–265
Watanabe M, Sawai H, Fukuda Y (1991a) Axonal regeneration of retinal ganglion cells in the cat geniculocortical pathway. Brain Res 560:330–333
Watanabe M, Sawai H, Fukuda Y (1991b) Morphology of retinal ganglion cells that regenerated axons along peripheral nerve graft in cats. Neurosci Res 15: S157-S164
Watanabe M, Sawai H, Rasminsky M, Sugioka M, Fukuda Y (1993a) Physiological properties of retinal ganglion cells that regenerated their axons into peripheral nerve grafts in cats. Invest Ophthalmol Vis Sci 34:1155
Watanabe M, Sawai H, Fukuda Y (1993b) Number, distribution and morphology of retinal ganglion cells with axons regenerated into peripheral nerve graft in adult cats. J Neurosci 13:2105–2117
Waxman SG, Swadlow HA (1977) The conduction properties of axons in central white matter. Prog Neurobiol 8:297–324
Williams RW, Chalupa LM (1983) An analysis of axon caliber within the optic nerve of the cat: evidence of size groupings and regional organization. J Neurosci 3:1554–1564
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Watanabe, M., Sawai, H. & Fukuda, Y. Myelination of regenerated optic fibers in peripheral nerve graft of adult cats. Exp Brain Res 98, 39–43 (1994). https://doi.org/10.1007/BF00229107
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DOI: https://doi.org/10.1007/BF00229107