AJP - Gastrointestinal and Liver Physiology, Vol 251, Issue 3 349-G353, Copyright © 1986 by American Physiological Society
Effect of trimebutine on intestinal motility and plasma motilin in the dog
P. Poitras, C. Honde, J. Havrankova, R. G. Lahaie, L. Trudel, R. Goyer, J. L. Junien and X. Pascaud
In a previous report, trimebutine was shown to induce premature periods of
phase III activity in fasting dogs, and its action was blocked by naloxone.
In this study, we observed that trimebutine (5 mg X kg-1 iv) could induce
premature phase IIIs in canine small intestine during interdigestive and
digestive periods; trimebutine-induced phase IIIs were migrating along the
small intestine faster than spontaneous activity fronts and;
trimebutine-induced phase IIIs were accompanied by sharp rises in
concentrations of plasma motilin. To further elucidate the
trimebutine-stimulatory mechanism, we verified its effects on the release
of various circulating peptides that influence intestinal motility:
short-interval blood sampling during trimebutine infusion revealed that
plasma motilin increases induced by trimebutine preceded the beginning of
phase III in proximal duodenum; and gastrin and insulin postprandial
releases were abolished by trimebutine. Therefore, trimebutine, by its
simultaneous but opposite effects on various peptides that individually
carry positive (e.g., motilin) or negative (e.g., gastrin and insulin)
influences on the generation of activity fronts, could alter the
equilibrium between stimulatory and inhibitory forces in such a way that,
in some circumstances (e.g., postprandial period), stimulatory mechanisms
become predominant.
