title: Alterations of vasoactive intestinal polypeptide receptors in allergic rhinitis.
abstract: BACKGROUND
  Vasoactive intestinal peptide (VIP) is one of the parasympathetic neurotransmitters involved in the regulation of airway mucus secretion. The biological functions of VIP are mediated through two receptors (vasoactive intestinal peptide receptor type 1 [VPAC1R] and type 2 [VPAC2R]). The purpose of this study was to determine the distribution of VIP receptors and to compare the level of VIP receptor expression in the nasal mucosa of patients with allergic rhinitis and normal controls.
  
  
  METHODS
  Inferior turbinate mucosal samples were obtained from 20 normal subjects and 20 patients with allergic rhinitis. VPAC1R and VPAC2R mRNA was extracted from the nasal mucosa, and then a reverse-transcription-polymerase chain reaction was performed. Sections were immunostained using specific antibodies for VIP receptors. Western blot analysis was used to analyze differences in the level of expression of VPAC1R and VPAC2R protein between patients with allergic rhinitis and normal controls.
  
  
  RESULTS
  The level of expression of VIP receptor mRNA and protein in patients with allergic rhinitis was significantly increased compared with normal nasal mucosa. VIP receptor immunoreactivity was detected on the nasal epithelium and submucosal glands in nasal specimens from both normal controls and patients with allergic rhinitis. In the epithelium from patients with allergic rhinitis, VIP receptor immunoreactivity was strong, whereas in the nasal epithelium from normal subjects it was faint.
  
  
  CONCLUSIONS
  These results suggest that an increased expression level of VIP receptors is one possible explanation for nasal hyperresponsiveness in patients with allergic rhinitis.
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Guro Hospital, Korea University College of Medicine, Seoul, South Korea.
authors.forename: Dae-Hyung
authors.initials: DH
authors.lastname: Kim
authors.forename: Il-Ho
authors.initials: IH
authors.lastname: Park
authors.forename: Jung-Sun
authors.initials: JS
authors.lastname: Cho
authors.forename: You-Mi
authors.initials: YM
authors.lastname: Lee
authors.forename: Hyuk
authors.initials: H
authors.lastname: Choi
authors.forename: Heung-Man
authors.initials: HM
authors.lastname: Lee
mesh_terms: D000328:Adult; D000818:Animals; D039741:Antigens, Dermatophagoides / Q000009:adverse effects; D005260:Female; D005786:Gene Expression Regulation / Q000276:immunology; D006801:Humans; D008297:Male; D009093:Mucus / Q000378:metabolism; D009297:Nasal Mucosa / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D039981:Pyroglyphidae; D051239:Receptors, Vasoactive Intestinal Peptide, Type II / Q000235:genetics / Q000378:metabolism*; D051238:Receptors, Vasoactive Intestinal Polypeptide, Type I / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012221:Rhinitis, Allergic, Perennial / Q000235:genetics / Q000276:immunology / Q000378:metabolism* / Q000503:physiopathology; D014660:Vasoactive Intestinal Peptide / Q000378:metabolism*
chemical_list: D039741:Antigens, Dermatophagoides; D051239:Receptors, Vasoactive Intestinal Peptide, Type II; D051238:Receptors, Vasoactive Intestinal Polypeptide, Type I; D014660:Vasoactive Intestinal Peptide