Intermittent myelination of small-diameter sciatic axons in Xenopus laevis.
Nerve fibres from the sciatic nerve of apparently normal Xenopus laevis were examined in teased preparations of living material and in series of cross-sections. Small-diameter fibres were found that were myelinated in a spatially intermittent fashion. In these fibres, the myelinated segments were separated by long non-myelinated regions that had a 1 : 1 relationship to the investing Schwann cell. It is estimated that at least 10% of the myelinated fibres with an external diameter of less than 5 micrograms were intermittently myelinated.
D000818:Animals; D001369:Axons / Q000473:pathology* / Q000648:ultrastructure; D005260:Female; D007365:Intercellular Junctions / Q000648:ultrastructure; D008854:Microscopy, Electron; D009413:Nerve Fibers, Myelinated / Q000473:pathology* / Q000648:ultrastructure; D012583:Schwann Cells / Q000648:ultrastructure; D012584:Sciatic Nerve / Q000503:physiopathology* / Q000648:ultrastructure; D014982:Xenopus laevis