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Myelin sheath

Synonym(s)

  • medullary sheath

Definition(s)

A fatty, axon-enwrapping sheath that serves to speed up neural conduction, formed by concentric layers of Schwann's cell (peripheral) or oligodendrocyte (CNS) membranes; loss or damage leads to severe loss of neural function, as in multiple sclerosis.

Definition from: CRISP Thesaurus via Unified Medical Language SystemThis link leads to a site outside Genetics Home Reference. at the National Library of Medicine

The lipid-rich sheath surrounding axons in both the central and peripheral nervous systems. The myelin sheath is an electrical insulator and allows faster and more energetically efficient conduction of impulses. The sheath is formed by the cell membranes of glial cells (Schwann cells in the peripheral and oligodendroglia in the central nervous system). Deterioration of the sheath in demyelinating diseases is a serious clinical problem.

Definition from: MeSH via Unified Medical Language SystemThis link leads to a site outside Genetics Home Reference. at the National Library of Medicine

The fatty substance that covers and protects nerves.

Definition from:  National Cancer Institute dictionaryThis link leads to a site outside Genetics Home Reference.

See also Understanding Medical Terminology.

 
Published: December 22, 2014