The fatty material made of lipid (fat) and protein that forms a protective sheath around some nerve fibres and increases the efficiency of nerve impulse transmission. (See also demyelination.)
A substance made up of protein and phospholipid that forms the sheath surrounding the axons of some neurons (see NEURON(E)). These are described as myelinated or medullated nerve ?bres, and electric impulses pass along them faster than along non-myelinated nerves. Myelin is produced by Schwann cells which occur at intervals along the nerve ?bre. (See MULTIPLE SCLEROSIS (MS).)
n. a complex material formed of protein and *phospholipid that is laid down as a sheath surrounding and insulating the *axons of certain neurons, known as myelinated (or medullated) nerve fibres. The material is produced and laid down in concentric layers by *Schwann cells at regular intervals along the nerve fibre (see illustrations). Myelinated nerves conduct impulses more rapidly than nonmyelinated nerves.
acute paralysis, dysphagia, and dysarthria resulting from damage to the myelin sheaths of nerve cells in the brainstem. It occurs most commonly as a complication of rapid correction of severe hyponatraemia (low serum sodium).... central pontine myelinolysis
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