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.
Farlex Partner Medical Dictionary © Farlex 2012

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.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012


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
Medical Eponyms © Farlex 2012
References in periodicals archive ?
The unmyelinated fibers showed the largest diameter (62%) varying from 0.25 to 0.75 [micro]m.
The grouping of unmyelinated fibers are enveloped by Schwann cell lamina and at periphery, may observe the bundles of collagen fibers (Fig.
In the nerve fibers axoplasm were seen neurofilaments, mitochondria, neurotubules and few unmyelinated fibers.
Rosenbluth says "We see now that an unmyelinated fiber will conduct.