unmyelinated fibers

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un·my·e·li·nat·ed fi·bers

fibers having no myelin covering, naked axons; in the central nervous system, represented by all axons lying in troughs of oligodendroglia, and in the peripheral nervous system, by all axons lying in troughs in a single Schwann cell (Schwann cell unit); slow-conducting fiber.

un·my·e·li·nat·ed fi·bers

(ŭn-mī'ĕ-li-nā-tĕd fī'bĕrz)
In the central nervous system, a fiber having no myelin covering; a naked axon; in the peripheral nervous system, represented by all axons lying in troughs in a single Schwann cell (Schwann cell unit); a slow conducting fiber.
Synonym(s): gray fibers, nonmedullated fibers, Remak fibers.


Robert, Polish-German anatomist and histologist, 1815-1865.
Remak band
Remak fibers - nerve fibers lacking a myelin sheath but, in common with others, enveloped by a sheath of Schwann cells. Synonym(s): unmyelinated fibers
Remak ganglia - (1) groups of nerve cells in the wall of the venous sinus where it joins the right atrium of the heart; - (2) autonomic ganglia in nerves of the stomach.
Remak nuclear division - direct division of the nucleus and cell, without the changes in the nucleus that occur in the ordinary process of cell reproduction. Synonym(s): amitosis
Remak plexus - a gangliated plexus of unmyelinated nerve fibers, derived chiefly from the superior mesenteric plexus, ramifying in the intestinal submucosa. Synonym(s): submucosal plexus
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In multiple sclerosis, "DT-MRI is the only technique that highlights some unmyelinated fibers, where conventional techniques don't allow you to see them," Dr.
The mice exhibited a significant reduction in tremors and neural symptoms posttransplant, and the investigators detected remyelination of previously unmyelinated fibers.
Unmyelinated fibers conduct very slowly (approximately 1 meter/second), while the speed of conduction in myelinated fibers depends on the total thickness of the fiber.