title: Myelinated nerve endings in human skin.
abstract: We used immunohistochemical techniques and confocal microscopy to study the morphometry of myelinated nerve endings in glabrous and hairy skin. A total of 30 healthy volunteers took part in this study designed to assess the possibility of obtaining reliable information on myelinated fibers using samples of hairy skin and to determine whether differences exist between myelinated terminations from different sites. We obtained consistent information on cutaneous myelinated terminations using hairy as well as glabrous skin samples. Myelinated endings from hairy and glabrous skin differ in density and distribution. However, from a comparison of our findings with data from nerve biopsy studies, we conclude that all cutaneous myelinated terminations are thinner terminal branches of large myelinated A beta fibers, whereas cutaneous terminations of small myelinated A delta fibers lose their myelin before entering the dermis and become indistinguishable from C-fiber terminations. The classic criteria, based on fiber size, used to distinguish myelinated fiber subgroups in sensory nerves are therefore not suitable for identifying myelinated terminations in the skin.
authors.affiliation: Neurology Division, Salvatore Maugeri Foundation IRCCS, Via Bagni Vecchi, 1 Telese Terme, BN 82037, Italy. vprovitera@fsm.it
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Provitera
authors.forename: Maria
authors.initials: M
authors.lastname: Nolano
authors.forename: Angela
authors.initials: A
authors.lastname: Pagano
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Caporaso
authors.forename: Annamaria
authors.initials: A
authors.lastname: Stancanelli
authors.forename: Lucio
authors.initials: L
authors.lastname: Santoro
mesh_terms: D000328:Adult; D005260:Female; D005385:Fingers / Q000294:innervation; D018859:Hair Follicle / Q000294:innervation / Q000502:physiology; D006801:Humans; D007150:Immunohistochemistry; D007866:Leg / Q000294:innervation; D008297:Male; D008465:Mechanoreceptors / Q000502:physiology / Q000648:ultrastructure; D018862:Merkel Cells / Q000502:physiology / Q000648:ultrastructure; D009413:Nerve Fibers, Myelinated / Q000502:physiology / Q000648:ultrastructure*; D036421:Nerve Fibers, Unmyelinated / Q000502:physiology / Q000648:ultrastructure; D010141:Pacinian Corpuscles / Q000502:physiology / Q000648:ultrastructure; D011984:Sensory Receptor Cells / Q000166:cytology* / Q000502:physiology; D012867:Skin / Q000294:innervation*; D013697:Thermosensing / Q000502:physiology; D013848:Thigh / Q000294:innervation; D014110:Touch / Q000502:physiology*