Markers of inflammation and influence of nitric oxide on platelet activation in the course of ulcerative colitis.

Ulcerative colitis is a non-specific inflammatory bowel disease of unknown etiology. We investigated whether severe form of ulcerative colitis may lead to increased number of platelets, changes in platelet parameters and their activation. To address our objectives, we measured concentrations of nitric oxide and markers of inflammation. We found increased number of low-volume platelets in a group of affected patients. However, their activity was not as high as expected. In addition to that we observed eight times higher concentration of nitric oxide in patients suffering from ulcerative colitis than in healthy individuals. Besides, severe form of the disease manifested itself with increased concentrations of interleukine 6, matrix metalloproteinase-9 and neopterin. Based on the results we propose that high amounts of nitric oxide inhibit platelet activation in severe form of ulcerative colitis. Moreover, our observations regarding interleukine 6, matrix metalloproteinase-9 and neopterin suggest that they may become useful markers of active form of ulcerative colitis.