1.   The concentration of myeloperoxidase, a neutrophil granule constituent, was measured in the perfusion fluid from sigmoid and rectal segments in patients with ulcerative colitis.

2.   The measurements were performed in the perfusion fluid obtained during regional perfusion of inflamed sigmoid and rectal segments.

3.   The total recovery of perfusion fluid was almost equal to that infused.

4.   The specificity of the assays applied to perfusion fluid was assured by dilution and by recovery experiments showing correlation to the standard curves.

5.   We found no significant relation between these scores and the measured substances in perfusion fluid.