Neurotensin stimulates defaecation.

Five normal adults defaecated within 2 1/2 hours of receiving neurotensin 13.5 pmol kg-1 min-1 for 30 min, whereas none did so after control infusions, in a double-blind study. Neurotensin caused borborygmi and production of stools which resembled the normal contents of the proximal and distal colon in terms of consistency and electrolyte content. This evidence suggests that neurotensin had a major effect on propulsive colonic motility. Blood neurotensin concentrations during infusion were about three times higher than normal postprandial concentrations, but plasma neurotensin is raised in some diseases associated with diarrhoea.