Vasoactive intestinal polypeptide (VIP) is a 28 amino acid peptide which is localised in both
the central and peripheral nervous system. In the human colon VIP is found in all layers and
the highest concentrations have been found in the myenteric plexus. It is known that VIP has
various effects on intestinal functions: i) it is a potent stimulant of mucosal water and
electrolyte secretion: ii) it is involved in the peristaltic reflex: and iii) plays an inhibitory role
on immune cell function. Based on these biological effects it has been hypothesized that the …

Results Overall plasma VIP concentrations in the UC patients were similar to those in the
controls. Significantly decreased concentrations of VIP were found in UC of rectum
compared to the normal tissue. However, both plasma VIP values and tissue concentrations
were found to be significantly lower in patients expressing minimal or mild active disease
according to clinical activity index (AI) and histological activity index (HAI), but marked
increase of plasma VIP was clear in UC patients with moderate or severe AI and HAI. There …