Decrease in binding for the neuropeptide VIP in response to marked inflammation of the mucosa in ulcerative colitis.

The neuropeptide vasoactive intestinal peptide (VIP) is involved in the neuroimmunomodulation of the intestine. In the present study, specimens from the sigmoid colon of ulcerative colitis (UC) and non-UC patients were examined for immunohistochemistry and in vitro receptor autoradiography. Marked occurrence of VIP binding was observed in the mucosa. However, there were very low levels of binding in areas showing pronounced inflammation/derangement. The study shows that marked derangement of the mucosa leads to a distinct decrease in VIP binding. Thus, it is possible that a decrease in trophic and anti-inflammatory VIP effects occurs in areas exhibiting a very marked inflammation.