Veterinary Histology and Embryology

AMYELINATED OR NON-MYELINATED NERVE FIBRES

• Sometimes called fibres of Remak. There is no medullary or myelin sheath Axis cylinder is very slender and the thin neurolemma sheath contains scattered nuclei of Schewann cells.
• There are no nodes of Ranvier, up to a dozen or more of these nerve fibres are enclosed by the cytoplasm of the same sheath of Schwann cells.
• Majority of the axons of automatic ganglia and the processes of many of the smaller cerebrospinal ganglia have no myelin sheath.
• In the CNS there are many non-myelinated nerve fibres (without neurolemma).