Peptidergic nerves in the colon of patients with ulcerative colitis

Background/Aims: The cause of impaired motility, such as diarrhea and toxic megacolon, in patients with ulcerative colitis is unknown. Neuropeptides h ave recently been shown to be a neurotransmitter in the non-adrenergic non- cholinergic inhibitory and excitatory nerves in the human gut. To clarify t he physiological significance of vasoactive intestinal polypeptide, substan ce P and neurotensin in the colon of patients with ulcerative colitis, we i nvestigated the enteric nerve responses on lesional and normal bowel segmen ts derived from patients with ulcerative colitis and patients who underwent colon resection for colonic cancers. Methodology: Twenty-four specimens were obtained from the lesional colon of 6 patients with ulcerative colitis (4 male, 2 female; ages 14-51 years, me an: 40.3 years). The patients with ulcerative colitis had chronic disease ( 4 with moderate disease, 2 with severe disease). Seventy-two specimens were obained from the normal colon of 10 patients with colonic cancer (8 men an d 2 women; ages 40-56 years, mean: 51.2 years). A mechanographic technique was used to evaluate in vitro muscle responses to these peptides of adrener gic and cholinergic nerves before and after treatment with various autonomi c nerve blockers. Results: (1) Peptidergic nerves such as vasoactive intestinal polypeptide, substance P, and neurotensin nerves were found to act on both normal colon and ulcerative colitis colon; (2) the colon with ulcerative colitis was mor e strongly innervated by vasoactive intestinal polypeptide nerves than the normal colon; (3) Substance P and neurotensin nerves act more weakly in the UC colon than the normal colon. Conclusions: These findings suggest that peptidergic nerves play an importa nt role in the impaired motility observed in patients with UC.