title: Histamine, xanthine oxidase generated oxygen-derived free radicals and Helicobacter pylori in gastroduodenal inflammation and ulceration.
abstract: OBJECTIVE
  The relationship between Helicobacter pylori (H. pylori), xanthine oxidase (XO)-induced oxygen derived free radicals (ODFR) and histamine in the induction of human gastroduodenal disorders was investigated.
  
  
  METHODS
  Histamine concentration, XO and xanthine dehydrogenase (XD) activities were measured in endoscopically obtained biopsies from 66 symptomatic patients.
  
  
  RESULTS
  H. pylori infection was associated with lower oxyntic and duodenal histamine in 'normal' controls (group N) (p < 0.002 and p < 0.05, respectively). Patients with gastroduodenal disease tended to have reduced mucosal concentration of histamine, but comparing H. pylori positive and negative patients, infection did not lead to a further fall in histamine concentration. H. pylori positive duodenal ulcer (DU) patients tended to have higher XO activity than group N (p = 0.051) and had a significantly lowered activity of XD, the precursor of XO (p' < 0.05). Histamine concentration at the ulcer-edge was lower while XO activity was higher than in the distant normal mucosa (p < 0.05, respectively). Gastritis (group GL) with H. pylori also had lower XD than H. pylori positive group N (p' < 0.025) but no corresponding rise in XO activity. In group N, duodenal mucosal histamine and XD activity were inversely related (Rs = -0.51, p < 0.025).
  
  
  CONCLUSIONS
  These findings support the hypothesis that histamine, xanthine oxidase related ODFR, and H. pylori may be closely associated in the manifestations of chronic duodenal ulcer.
authors.affiliation: Department of Gastrointestinal Surgery, Imperial College School of Medicine, Hammersmith Hospital, London, UK. aben-ham@rpms.ac.uk
authors.forename: A
authors.initials: A
authors.lastname: Ben-Hamida
authors.forename: W K
authors.initials: WK
authors.lastname: Man
authors.forename: N
authors.initials: N
authors.lastname: McNeil
authors.forename: J
authors.initials: J
authors.lastname: Spencer
mesh_terms: D000328:Adult; D000368:Aged; D004724:Endoscopy; D005260:Female; D005753:Gastric Mucosa / Q000378:metabolism; D016481:Helicobacter Infections / Q000378:metabolism*; D016480:Helicobacter pylori; D006632:Histamine / Q000378:metabolism*; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D010437:Peptic Ulcer / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism*; D014968:Xanthine Dehydrogenase / Q000378:metabolism; D014969:Xanthine Oxidase / Q000378:metabolism*
chemical_list: D017382:Reactive Oxygen Species; D006632:Histamine; D014968:Xanthine Dehydrogenase; D014969:Xanthine Oxidase