title: Gut mucosal granulocyte activation precedes nitric oxide production: studies in coeliac patients challenged with gluten and corn.
abstract: OBJECTIVE
  To elucidate the dynamics of nitric oxide (NO) production induced by rectal gluten challenge and the relation between NO production and mucosal granulocyte activation.
  
  
  METHODS
  Release of rectal NO was measured in 13 patients with coeliac disease and in 18 controls before and after rectal wheat gluten challenge. Rectal gas was collected with a rectal balloon using a newly developed instrument/technique, the "mucosal patch technique". The instrument allows simultaneous measurements of concentrations of granulocyte mediators in the rectal mucosa. We measured myeloperoxidase (MPO), eosinophil cationic protein (ECP), and histamine. For comparison, we made similar measurements after corn (maize) gluten challenge.
  
  
  RESULTS
  In all coeliac patients rectal NO concentration increased after gluten challenge and reached a peak after 15 hours (mean 9464 (SEM 2393) parts per billion (ppb); range 250-24982). The maximum MPO and ECP increase occurred five hours after challenge. A correlation was found between mucosal MPO and NO production at 15 hours. Six of the patients showed an increase in NO production 15 hours after rectal corn gluten challenge but this was much smaller than after gluten challenge. No increases were seen in the control group after either challenge.
  
  
  CONCLUSIONS
  Mucosal activation of neutrophils and eosinophils precedes pronounced enhancement of mucosal NO production after rectal wheat gluten challenge in patients with coeliac disease. Some of our coeliac patients displayed signs of an inflammatory reaction, as measured by NO and granulocyte markers, after rectal corn gluten challenge.
authors.affiliation: Department of Medical Sciences, Uppsala University, Department of Gastroenterology, Uppsala University Hospital, 75185 Uppsala, Sweden. gudjon.kristjansson@medsci.uu.se
authors.forename: G
authors.initials: G
authors.lastname: Kristjánsson
authors.forename: M
authors.initials: M
authors.lastname: Högman
authors.forename: P
authors.initials: P
authors.lastname: Venge
authors.forename: R
authors.initials: R
authors.lastname: Hällgren
mesh_terms: D000285:Administration, Rectal; D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D016022:Case-Control Studies; D002446:Celiac Disease / Q000378:metabolism*; D047150:Eosinophil Cationic Protein / Q000378:metabolism; D004804:Eosinophils / Q000378:metabolism; D005260:Female; D005983:Glutens / Q000008:administration & dosage / Q000494:pharmacology*; D006632:Histamine / Q000378:metabolism; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009504:Neutrophils / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism*; D009195:Peroxidase / Q000378:metabolism; D012007:Rectum / Q000378:metabolism*; D003313:Zea mays
chemical_list: D009569:Nitric Oxide; D005983:Glutens; D006632:Histamine; D009195:Peroxidase; D047150:Eosinophil Cationic Protein