title: Enteric neurons of the esophagus: an immunohistochemical study using donated elderly cadavers.
abstract: OBJECTIVE
  To describe and discuss the normal anatomy and function of enteric neurons in the esophagus of aged individuals.
  
  
  METHODS
  We examined ganglion cells in esophagus specimens obtained from 15 elderly cadavers without any macroscopic pathology in the mediastinum and abdomen. Neuronal nitric oxide synthase and vasoactive intestinal polypeptide were used as parasympathetic nerve markers, and tyrosine hydroxylase as a sympathetic nerve marker.
  
  
  RESULTS
  The thoracic and abdominal esophagus contained a well-developed myenteric nerve plexus (S100 protein-positive area) in the intermuscular layer: 0.02-0.03 mm2per 1-mm length of the circular esophageal wall. The cervical esophagus usually contained no ganglion cells. The number of parasympathetic ganglion cells was maximal in the upper or middle thoracic esophagus (mean 18-23 cells per section), whereas sympathetic cells were considerably less numerous at any sites (mean 1-3 cells).
  
  
  CONCLUSIONS
  In comparison with previous data from elderly cadavers, the esophagus carried much fewer ganglion cells than the intestine and colon; sympathetic cells were particular less numerous. Esophageal smooth muscle exhibits a unique mode of peristalsis characterized by a rebound contraction with a long latency after stimulation. This type of peristalsis appears to be regulated by inhibitory, nNOS-positive nerves with a sparse distribution, which seems to account for the long-span peristalsis unique to the esophagus. The extreme sparsity of ganglion cells in the cervical esophagus suggests that enteric neuron-integrated peristalsis, like that in the intestine and colon, is unlikely. Surgical treatment of the esophagus is likely to change or impair these unique features.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, 980-8574, Japan.
authors.forename: Ai
authors.initials: A
authors.lastname: Hirano-Kawamoto
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, 980-8574, Japan. y-honkura@orl.med.tohoku.ac.jp.
authors.forename: Yohei
authors.initials: Y
authors.lastname: Honkura
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, 980-8574, Japan.
authors.forename: Yuta
authors.initials: Y
authors.lastname: Kobayashi
authors.affiliation: Department of Anatomy, Tokyo Dental College, 2-9-18 Misaki-cho, Chiyoda-ku, Tokyo, 101-0061, Japan.|Division of Internal Medicine, Iwamizawa Asuka Hospital, 297-13 Shibun-cho, Iwamizawa, Hokkaido, 068-0833, Japan.
authors.forename: Gen
authors.initials: G
authors.lastname: Murakami
authors.affiliation: Department of Anatomy, Tokyo Dental College, 2-9-18 Misaki-cho, Chiyoda-ku, Tokyo, 101-0061, Japan.
authors.forename: Shin-Ichi
authors.initials: SI
authors.lastname: Abe
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, 980-8574, Japan.
authors.forename: Yukio
authors.initials: Y
authors.lastname: Katori
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000032:analysis; D002102:Cadaver; D004947:Esophagus / Q000294:innervation*; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods*; D008297:Male; D009197:Myenteric Plexus / Q000033:anatomy & histology*; D009474:Neurons; D052248:Nitric Oxide Synthase Type I / Q000032:analysis; D014446:Tyrosine 3-Monooxygenase / Q000032:analysis; D014660:Vasoactive Intestinal Peptide / Q000032:analysis
chemical_list: D015415:Biomarkers; D014660:Vasoactive Intestinal Peptide; D052248:Nitric Oxide Synthase Type I; D014446:Tyrosine 3-Monooxygenase
keywords: Enteric neuron; Esophagus; Ganglion cells; Human elderly cadavers; Immunohistochemistry; Parasympathetic nerve