Summary
The electron microscopy of changes at Schmidt-Lanterman incisures in Wallerian degeneration has been described only briefly previously. We have demonstrated that the changes up to 36 h after nerve crush are chiefly peri-incisural. At 12h and 24h ‘incisural dilatation’ consisted of an intraperiod line separation of peri-incisural myelin lamellae, which began among inner (adaxonal) lamellae extending later to outer (abaxonal) lamellae. The incisure itself showed little or no change. At 36 h, ovoid formation was apparent in most fibres. The sites of fibre cleavage to form ovoids occurred adjacent to incisures at the focal regions of myelin lamellae separation. Even within ovoids the incisures themselves remained intact at 36 h.
The fine structural changes at incisures following nerve crush provide an understanding of the increased perceptibility of incisures by light microscopy during early Wallerian degeneration.
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References
Allt, G.: Pathology of the peripheral nerve. In: The peripheral nerve, Ch. 13. London: Chapman and Hall 1976
Cajal, S. R.: Degeneration and regeneration of the nervous system, Vol. 1, pp. 6, 67–74. London: Oxford University Press 1928
Ghabriel, M. N., Allt, G.: The role of Schmidt-Lanterman incisures in Wallerian degeneration: I. A quantitative teased fibre study. Acta Neuropathol. (Berl.)48, 83–93 (1979a)
Ghabriel, M. N., Allt, G.: Schmidt-Lanterman incisures in remyelination: a quantitative and electron microscope study. J. Anat. (in press) (1979b)
Glimstedt, G., Wohlfart, G.: Electron microscopic studies of peripheral nerve regeneration. Lunds Universitets Arsskrift N. F. Avd.16, 1–63 (1960)
Hall, S. M., Williams, P. L.: Studies on the ‘incisures’ of Schmidt and Lanterman. J. Cell Sci.6, 767–792 (1970)
Hiscoe, H. B.: Distribution of nodes and incisures in normal and regenerated nerve fibres. Anat. Rec.99, 447–475 (1947)
Howell, W. H., Huber, G. C.: A physiological, histological and clinical study of the degeneration and regeneration in peripheral nerve fibres after severance of their connections with the nerve centres. J. Physiol. (Lond.)13, 335–406 (1892)
Robertson, J. D.: The ultrastructure of Schmidt-Lanterman clefts and related shearing defects of the myelin sheath. J. Biophys. Biochem. Cytol.4, 39–53 (1958)
Schnapp, B., Mugnaini, E.: The myelin sheath: electron microscopic studies with thin sections and freeze-fracture. In: Golgi centennial symposium, Proc., pp. 209–233. New York: Raven Press 1975
Singer, M.: Penetration of labelled amino acids into the peripheral nerve fibre from surrounding body fluids. In: Growth of the nervous system, pp. 200–219. London: Churchill 1968
Singer, M., Bryant, S.: Movements in the myelin Schwann sheath of the vertebrate axon. Nature221, 1148–1150 (1969)
Sotnikov, O. S.: Structure of Schmidt-Lanterman incisures. Fed. Proc. Fed. Am. Soc. Exp. Biol.25, 204–210 (1965)
Spencer, P. S., Thomas, P. K.: Ultrastructural studies of the dying-back process. 2. Schwann cell oligodendroglial cell sequestration and removal of organelles from normal and diseased axons. J. Neurocytol.3, 763–783 (1974)
Webster, H. de F.: The relationship between Schmidt-Lanterman incisures and myelin segmentation during Wallerian degeneration. Ann. NY Acad. Sci.122, 29–38 (1965)
Williams, P. L., Hall, S. M.: In vivo observations on mature myelinated nerve fibres of the mouse. J. Anat.107, 31–38 (1970)
Williams, P. L., Hall, S. M.: Prolonged in vivo observations of normal peripheral nerve fibres and their acute reactions to crush and deliberate trauma. J. Anat.108, 397–408 (1971a)
Williams, P. L., Hall, S. M.: Chronic Wallerian degeneration — an in vivo and ultrastructural study. J. Anat.109, 487–503 (1971b)
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Ghabriel, M.N., Allt, G. The role of Schmidt-Lanterman incisures in Wallerian degeneration. Acta Neuropathol 48, 95–103 (1979). https://doi.org/10.1007/BF00691150
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DOI: https://doi.org/10.1007/BF00691150