Fig. 1.

The mucosal patch technique for measurement of the inflammatory condition of the rectal mucosa is illustrated. The instrument used is a plastic catheter with a silicon balloon at the end of the catheter, with three patches of highly absorptive cellulose material attached to the balloon. The figure illustrates when the instrument is positioned in the rectal ampulla and the balloon is inflated with air (60–80 ml), allowing the patches to be in contact with the mucosa. After 20 min the balloon is deflated and the air is collected in glass syringe for analysis of nitric oxide (NO). After removal of the catheter the patches are cut off and immediately placed in 2 ml of 0·3% N-cetyl-N,N,N-trimethyl ammonium bromide (CTAB) to extract the contents.