Effects of sildenafil on rat irritable bowel syndrome

Background: Irritable bowel syndrome (IBS) is a disorder with unknown pathophysiology, although it would appear that stress of different types plays an important role in the onset and development of the disorder. It affects 10-15% of the general population. Currently, anticholinergics and prokinetics are the main therapies. Objective: The objective of this study was to examine the effects of sildenafil in an animal model of IBS. Methods: IBS was induced in rats using the wrap-restraint method and sildenafil was administered intragastrically by gavage at doses of 0.5, 1 and 5mg/kg. Gastric emptying, small bowel transit and fecal excretion (index of large intestine motility) as well as concentrations of cyclic nucleotides (cGMP and cAMP) and total antioxidant capacity in the large intestine were determined. Results: Sildenafil at all doses used (0.5, 1 and 5mg/kg) significantly reduced gastric emptying up to 120min postdrug administration. All doses (0.5, 1 and 5mg/kg) of sildenafil dose-dependently reduced...