Migrating Motor Complex in Colectomized Ileo Stoma Patients

Abstract:  In colectomized patients with ileo stoma, the reflex modulation of small intestinal functions is disturbed, resulting in high enteric stoma outputs and malabsorption. Serotonin has a pivotal role in initiating motor and secretory reflexes involving activation of neuronal 5-HT3 and smooth muscle muscarinic receptors. We aimed to evaluate the effect of 5-hydroxytryptamine (5-HT), ondansetron and atropine on fasting and stimulated antro-duodeno-jejunal migrating motor complex (MMC) in colectomized patients with ileo stoma compared with healthy subjects. Manometric recordings were obtained in a blinded, age- and gender-matched design. The effects of either standard meal or intravenous 5-HT (10 nmol/kg/min.) treatment with pre-treatment of saline (placebo) or ondansetron (250 μg/kg) or atropine (10 μg/kg) were compared. Adverse effects, blood pressure, heart rate and electrocardiographic data were also evaluated. 5-HT increased the frequency (threefold) and migration velocity (twofold) of MMC phase III in both experimental groups. Ondansetron reduced 5-HT-induced frequency of MMC phase III in patients (p   0.05). Atropine did not change fasting MMC in healthy subjects (p > 0.05). We conclude that 5-HT is a stimulator of MMC phase III and that ondansetron reduces the 5-HT-induced MMC phase III without affecting fasting or postprandial properties in colectomized patients with ileo stoma. Similar effects were observed for 5-HT and atropine in healthy subjects.