Previous inflammation alters the response of the rat colon to stress

Background & Aims: Patients with inflammatory bowel tween stressful life events and exacerbations of IBD have disease have symptoms of irritable bowel syndrome been criticized for methodological flaws. 3 Two recent (IBS) with a higher than expected prevalence.Stress prospective studies have yielded conflicting results.Duffy is an important factor in the pathogenesis of IBS.Thus, et al. found a positive temporal association between stress previous inflammation may predispose to IBS by renderand exacerbations during a 6-month study of 124 paing the bowel more susceptible to the impact of stress.tients with IBD 4 and observed little or no lag time be-The aim of this study was to examine the effect of tween the stress and relapse of disease. 5 In contrast, North previous colitis on stress-induced responses in rats.et al. found no relationship between life events and re-Methods: Acute colitis was induced in rats by intrareclapses of IBD in 32 patients followed up for 2 years. 3 tal administration of trinitrobenzene sulfonic acid These studies relied heavily 4 or exclusively 5 on symptom (TNBS), and the rats were allowed to recover for 6 reporting by patients; it is therefore unclear whether the weeks before application of mild restraint stress for outcomes reflected the inflammatory process or functional 3 consecutive days.In vitro measurements included myeloperoxidase activity, plasma corticosterone levsymptoms that are known to occur with high prevalence els, interleukin 1b messenger RNA expression, and in patients with IBD in remission. 6 [ 3 H]noradrenaline release from the myenteric plexus. However, observations in animals suggest that thereResults: Six weeks after administration of TNBS, stress may be an association between stress and colitis.Gibbon caused a significant increase in myeloperoxidase activmonkeys subjected to social upheaval developed a fatal ity in TNBS-treated rats but not in stressed controls; colitis, 7 and it is speculated that the colitis found in plasma corticosterone responses were similar.Stress Abbreviations used in this paper: IBS, irritable bowel syndrome; for review), but there remains uncertainty regarding the IL, interleukin; MPO, myeloperoxidase; TNBS, trinitrobenzene sulrole of stress in precipitating exacerbations of ulcerative fonic acid.colitis or Crohn's disease.