Oesophageal epithelial innervation in health and reflux oesophagitis

Background-The response of the oesophagus to refluxed gastric contents is l ikely to depend on intact neural mechanisms in the oesophageal mucosa. The epithelial innervation has not been systematically evaluated in health or r eflux disease. Aims-To study oesophageal epithelial innervation in controls, and also infl amed and non-inflamed mucosa in patients with reflux oesophagitis and heale d oesophagitis. Patients-Ten controls, nine patients with reflux oesophagitis, and five pat ients with healed oesophagitis. Methods-Oesophageal epithelial biopsy specimens were obtained at endoscopy. The distribution of the neuronal marker protein gene product 9.5 (PGP), an d the neuropeptides calcitonin gene related peptide (CGRP), neuropeptide Y (NPY), substance P (SP), and vasoactive intestinal peptide (VIP) were inves tigated by immunohistochemistry. Density of innervation was assessed by the proportion of papillae in each oesophageal epithelial biopsy specimen cont aining immunoreactive fibres (found in the subepithelium and epithelial pap illae, but not penetrating the epithelium). Results-The proportion of papillae positive for PGP immunoreactive nerve fi bres was significantly increased in inflamed tissue when compared with cont rols, and non-inflamed and healed tissue. There was also a significant incr ease in VIP immunoreactive fibres within epithelial papillae. Other neurope ptides showed no proportional changes in inflammation. Conclusions-Epithelial biopsy specimens can be used to assess innervation i n the The innervation of the mucosa is not altered in non-inflamed tissue o f patients with oesophagitis but alters in response to inflammation, where there is a selective increase (about three- to fourfold) in VIP containing oesophagus. oesophageal nerves.