Effects of a serotonin 5-HT4 receptor antagonist SB-207266 on gastrointestinal motor and sensory function in humans. Issue 5 (1st November 2000)

• Record Type: Journal Article
• Authors: Bharucha, A E; Camilleri, M; Haydock, S; Ferber, I; Burton, D; Cooper, S; Tompson, D; Fitzpatrick, K; Higgins, R; Zinsmeister, A R
• Is Part Of: Gut. Volume 47:Issue 5(2000)
• Page Start: 667
• Page End: 674
• Publication Date: 2000-11-01
• Subjects: 5-HT4 receptors -- colon transit -- gastrointestinal motor function -- gastrointestinal sensory function; Gastroenterology -- Periodicals; 616.33
• DOI: 10.1136/gut.47.5.667
• Languages: English
• ISSNs: 0017-5749

Abstract

Abstract : BACKGROUND: Serotonin 5-HT4 receptors are located on enteric cholinergic neurones and may regulate peristalsis. 5-HT4 receptors on primary afferent neurones have been postulated to modulate visceral sensation. While 5-HT4 agonists are used as prokinetic agents, the physiological role of 5-HT4 receptors in the human gut is unknown. AIMS: Our aim was to characterise the role of 5-HT4 receptors in regulating gastrointestinal motor and sensory function in healthy subjects under baseline and stimulated conditions with a 5-HT4 receptor antagonist. METHODS: Part A compared the effects of placebo to four doses of a 5-HT4 receptor antagonist (SB-207266) on the cisapride mediated increase in plasma aldosterone (a 5-HT4 mediated response) and orocaecal transit in 18 subjects. In part B, 52 healthy subjects received placebo, or 0.05, 0.5, or 5 mg of SB-207266 for 10–12 days; gastric, small bowel, and colonic transit were measured by scintigraphy on days 7–9, and fasting and postprandial colonic motor function, compliance, and sensation during distensions were assessed on day 12. RESULTS: Part A: 0.5, 5, and 20 mg doses of SB-207266 had significant and quantitatively similar effects, antagonising the cisapride mediated increase in plasma aldosterone and acceleration of orocaecal transit. Part B: SB-207266 tended to delay colonic transit (geometric centre of isotope at 24 (p=0.06) and 48 hours (p=0.08)), but did not have dose related effects on transit, fasting or postprandial colonic motor activity, compliance, or sensation. CONCLUSION: 5-HT4 receptors are involved in the regulation of cisapride stimulated orocaecal transit; SB 207266 tends to modulate colonic transit but not sensory functions or compliance in healthy human subjects.