Fasting plasma nitric oxide products in coeliac disease.
OBJECTIVE
In coeliac disease, inducible nitric oxide synthase activity in the duodenal mucosa is greatly increased, resulting in increased production of nitric oxide. We investigated whether this resulted in increased plasma concentrations of its stable end products (nitrate/nitrite: NOx).


METHODS
Fasting plasma NOx was determined in 66 patients attending for upper gastrointestinal endoscopy. Of these, 21 had coeliac disease (nine were on a gluten-free diet). The remainder had a variety of other gastrointestinal disorders. NOx was determined using the Griess reaction. Distal duodenal biopsies for coeliac patients were graded according to the Marsh score.


RESULTS
Patients with untreated coeliac disease had a higher fasting NOx concentration (mean 117.5 microM) than either those with coeliac disease taking a gluten-free diet (mean 71.2 microM) or those with other diseases (mean 33.5 microM; one-way analysis of variance, P < 0.001). Coeliac patients with higher fasting NOx concentrations had more marked histological changes (P < 0.05).


CONCLUSIONS
Fasting plasma NOx is significantly elevated in untreated coeliac disease and correlates with histological grade. The potential clinical utility of serial NOx measurements to monitor improvement on a gluten-free diet requires further study.
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D015415:Biomarkers / Q000097:blood; D002446:Celiac Disease / Q000097:blood* / Q000178:diet therapy / Q000473:pathology; D004386:Duodenum / Q000201:enzymology; D005215:Fasting / Q000097:blood*; D005260:Female; D005773:Gastroscopy; D005983:Glutens / Q000008:administration & dosage; D006801:Humans; D008297:Male; D008875:Middle Aged; D009566:Nitrates / Q000097:blood; D009569:Nitric Oxide / Q000096:biosynthesis*; D019001:Nitric Oxide Synthase / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II; D009573:Nitrites / Q000097:blood
D015415:Biomarkers; D009566:Nitrates; D009573:Nitrites; D009569:Nitric Oxide; D005983:Glutens; C496319:NOS2 protein, human; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II