myelin sheath

American  

noun

Anatomy.

1. a wrapping of myelin around certain nerve axons, serving as an electrical insulator that speeds nerve impulses to muscles and other effectors.

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Etymology

Origin of myelin sheath

First recorded in 1895–1900

Example Sentences

See Examples For:

myelin sheath

MS is a disease of the brain and central nervous system, in which the immune system mistakenly attacks the fatty myelin sheath that normally protects the nerves, like insulation around electric wires.

From BBC ● May 29, 2026

To test this idea, Zhang and his team examined whether the mutation could protect the myelin sheath.

From Science Daily ● Apr. 15, 2026

In MS, the immune system mistakenly attacks the myelin sheath, a protective layer that insulates nerve fibers.

From Science Daily ● Oct. 11, 2025

In both aging mice and mice mimicking MS, the ESI1 treatment prompted myelin sheath production and improved lost neurological function.

From Science Daily ● May 2, 2024

When the organoids were exposed to ESI1, the treatment extended the myelin sheath of myelinating cells, the study reports.

From Science Daily ● May 2, 2024