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Nerve Fibers, Unmyelinated MeSH Descriptor Data 2025
A class of nerve fibers as defined by their nerve sheath arrangement. The AXONS of the unmyelinated nerve fibers are small in diameter and usually several are surrounded by a single MYELIN SHEATH. They conduct low-velocity impulses, and represent the majority of peripheral sensory and autonomic fibers, but are also found in the BRAIN and SPINAL CORD.
A class of nerve fibers as defined by their nerve sheath arrangement. The AXONS of the unmyelinated nerve fibers are small in diameter and usually several are surrounded by a single MYELIN SHEATH. They conduct low-velocity impulses, and represent the majority of peripheral sensory and autonomic fibers, but are also found in the BRAIN and SPINAL CORD.
Type C fibers are peripheral unmyelinated nerve fibers in which several AXONS are surrounded by a single Schwann cell (SCHWANN CELLS). They constitute more than half of the peripheral sensory nerve fibers as well as all the postganglionic autonomic fibers.