Immunohistochemical localization of gamma and beta subunits of epithelial Na+ channel in the rat molar tooth pulp.
The distribution of gamma and beta subunits of epithelial Na(+) channel (ENaC), markers for low-threshold mechanoreceptors in peripheral tissues, was examined in the tooth pulp. In the root pulp, gammaENaC- and betaENaC-immunoreactive (IR) nerve fibers showed a thick smooth appearance. These nerve fibers ascended toward the pulp horn and formed subodontoblastic nerve plexuses. Immunoelectron microscopic method revealed that 63% of axons were immunoreactive for gammaENaC in the root pulp. Virtually all myelinated axons showed gammaENaC-IR (97%), whereas unmyelinated axons were mostly devoid of it (12%). These findings suggest that myelinated tooth pulp nociceptors respond to mechanical stimuli.
Ichikawa
H
H
Department of Oral Function and Anatomy, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 700-8525, Japan. hiroichi@md.okayama-u.ac.jp
Fukuda
T
T
Terayama
R
R
Yamaai
T
T
Kuboki
T
T
Sugimoto
T
T
D000818:Animals; D003782:Dental Pulp / Q000294:innervation / Q000502:physiology*; D053503:Epithelial Sodium Channels; D007150:Immunohistochemistry; D008297:Male; D016253:Microscopy, Immunoelectron; D008963:Molar / Q000294:innervation / Q000502:physiology*; D009412:Nerve Fibers / Q000502:physiology; D009619:Nociceptors / Q000187:drug effects; D010812:Physical Stimulation; D051381:Rats; D017207:Rats, Sprague-Dawley; D015222:Sodium Channels / Q000378:metabolism*
D053503:Epithelial Sodium Channels; D015222:Sodium Channels