CONFIRMATION OF NITRIC-OXIDE SYNTHESIS IN ACTIVE ULCERATIVE-COLITIS BY INFRARED DIODE-LASER SPECTROSCOPY

Background: The synthesis of nitric oxide (NO) in the colonic mucosa o f patients affected by ulcerative colitis (UC) has been previously inv estigated using indirect measurements of enzyme activity and non-speci fic measurements of luminal NO gas. The aim of this study was to deter mine unequivocally if luminal NO gas in active UC is present in greate r concentrations than in healthy control subjects. Methods: Luminal ga s was collected from eight patients with active UC and eight healthy v olunteers. NO gas concentration was measured using diode laser spectro scopy. Results: NO gas was detected in four of eight patients with act ive UC (range 0.13-1.1 nmol) and none of the healthy control subjects. Conclusion: NO gas is present in greater concentrations in patients w ith active UC than in control subjects. This supports the view that mu cosal NO synthesis is increased in ulcerative colitis.