Visceral hypersensitivity and low grade mucosal inflammation are frequently observed in a subpopulation of irritable bowel syndrome (IBS) patients. The responsible mechanism is unclear. Resolvins are a novel class of anti-inflammatory lipid mediators that regulate resolution of inflammation and pain. We hypothesize that resolvin D1 (RvD1) synthesis is reduced in IBS-D colonic mucosa and contribute to the development of visceral hypersensitivity.