ABSTRACT
Visceral pain is the number one reason for patient visits in the United States. In many cases, visceral pain is not associated with obvious pathology. For example, irritable bowel syndrome (IBS), which can occur following inammation (Gwee et al. 1996; Collins et al. 1999; Bercik et al. 2005), is a diagnosis of exclusion because its hallmarks include abdominal pain accompanied by diarrhea or constipation in the absence of any obvious pathophysiology. It has been proposed that one of the contributing factors to these persistent pain states is chronic hypersensitivity of visceral sensory neurons (Wood 2002; Cenac et al. 2007).
