motilin and Colonic-Diseases

Previous studies showed increased plasma motilin and substance P concentrations and accelerated motor function in the small bowel and colon in patients with carcinoid diarrhea. Octreotide is beneficial in patients with carcinoid syndrome. Our hypothesis was that octreotide inhibits accelerated motility and gut neuropeptides in carcinoid syndrome.. In 12 patients with metastatic carcinoid syndrome, we investigated the effect of octreotide 50 microg s.c. t.i.d (n = 6) or placebo (n = 6) on postprandial symptoms, GI transit, colonic motility, and circulating levels of selected circulating peptides and amines.. Octreotide reduced postprandial flushing (p = 0.03) but not pain. Octreotide significantly retarded overall colonic transit and proximal colonic emptying (p < 0.05); it tended to prolong small bowel transit time (p = 0.13) and to reduce postprandial colonic tone (p = 0.08) compared with placebo. Octreotide also reduced circulating levels of peptide YY, neurotensin, vasoactive intestinal polypeptide, and substance P but had no effect on plasma motilin, neuropeptide Y, calcitonin gene-related peptide, or histamine after meal ingestion.. Octreotide ameliorates gut motor dysfunctions that characterize carcinoid diarrhea; the potential role of specific antagonism of serotonin, substance P, and vasoactive intestinal polypeptide alone or in combination with agents that inhibit their release in carcinoid diarrhea deserves further study.

Topics: Aged; Antineoplastic Agents, Hormonal; Calcitonin Gene-Related Peptide; Colon; Colonic Diseases; Diarrhea; Digestion; Double-Blind Method; Female; Flushing; Gastrointestinal Agents; Gastrointestinal Motility; Gastrointestinal Transit; Histamine; Humans; Intestine, Small; Male; Malignant Carcinoid Syndrome; Middle Aged; Motilin; Neuropeptide Y; Neuropeptides; Neurotensin; Octreotide; Peptide YY; Placebos; Serotonin Antagonists; Substance P; Vasoactive Intestinal Peptide

In order to investigate the possible involvement of gastrointestinal hormones in functional disorders of the digestive tract, serum motilin, neurotensin and gastrin levels in their response to oral intake of fat and glucose were examined in patients with irritable colon syndrome and dumping syndrome. The following results were obtained. (1) Basal serum motilin levels were higher in patients with irritable colon syndrome than in normal subjects, and remained high after ingestion of either 50 g of butter or 50 g of glucose. (2) No consistent response in serum neurotensin levels was found in patients with irritable colon syndrome or in normal subjects. (3) An immediate increase in serum gastrin levels was found in response to fat ingestion both in patients with irritable colon syndrome and in normal subjects, but there was no difference between these two groups. (4) In a patient with typical dumping syndrome, a markedly high level of fasting serum motilin was found, and the level increased further after the oral intake of glucose. These findings suggest that motilin may be involved in the irritable colon syndrome and dumping syndrome.

Topics: Adult; Colonic Diseases; Colonic Diseases, Functional; Dietary Fats; Fasting; Gastrins; Gastrointestinal Hormones; Glucose; Humans; Motilin; Neurotensin