Cutaneous nerve fiber

Cutaneous nerve fibers are the terminal axons of peripheral neurons that innervate the skin. They arise from the dorsal root ganglia of the spinal cord and traverse the dermis to form free nerve endings in the epidermis and dermis, providing sensory innervation (pain, temperature, touch, itch) and autonomic regulation (sweat glands, vasomotor tone, arrector pili muscle) to cutaneous tissues[1][3][4][10]. These fibers include:\n- Unmyelinated C-fibers (sense pain, temperature, itch, autonomic function)\n- Thinly myelinated Aδ-fibers (sense pain and temperature)\n- Myelinated Aβ-fibers (mechanoreception, less common in superficial skin)\n\nSensory cutaneous nerve fibers mediate nociceptive, thermal, and mechanosensory input; autonomic fibers regulate blood flow, sweating, and piloerection via neurotransmitters and neuropeptides such as acetylcholine, norepinephrine, substance P, CGRP, neuropeptide Y, and vasoactive intestinal peptide[2][3][6]. Pathology in these fibers—such as degeneration or dysfunction—plays a key role in small fiber neuropathy and other neurocutaneous disorders. Diagnostic skin biopsies frequently assess intraepidermal nerve fiber density as a marker for these diseases[1][6].\n\nAdditional notes:\n- Cutaneous nerve fiber is not a single molecular target, receptor, or protein; rather, it refers to a heterogeneous population of nerve terminals in the skin, so it cannot be therapeutically targeted as a unitary entity[1][2][3][10].\n- Various specialized types exist, e.g., intraepidermal nerve fiber, perivascular nerve fiber, periadnexal nerve fiber.\n- Subtypes release or respond to a broad range of neuromediators and neurotrophic factors in the local skin environment[3][6][9].

Other names

Cutaneous nerve fibersEpidermal nerve fiberDermal nerve fiberIntraepidermal nerve fiber