BIOLOGICAL INTERACTION OF STRESS AND IRRITABLE BOWEL SYNDROME

A variety of stressors play a role in the development of irritable bowel syndrome. Irritable bowel syndrome is a biopsychosocial disorder that results from dysregulation of central or enteric nervous system function. The physiological effects of psychological and physical stressors on gut function and brain-gut interactions are mediated by outputs of the emotional motor system in terms of autonomic, neuroendocrine, attentional, and pain modulatory responses. Certain investigational studies reported to date indicate that the activation of CRF1 pathways may result in a combination of effects that are key features of symptoms in some irritable bowel syndrome patients. These include stimulation of colonic motility, defecation or watery diarrhea, gut hypersensitivity that increases the perception of stimuli within the bowel, focused attention (hypervigilance) toward the gut sensations, and mast cell activation. Blocking the CRF1 receptors may alleviate all these effects. Stress thus can be included in an integrative model explaining the pathophysiology of functional bowel disorder. Advances in the understanding of the relationship between stress and visceral perception may constitute a basis for a therapeutic approach of functional bowel disorders targeted on the central nervous system.