Sex Differences of Brain Serotonin Synthesis in Patients with Irritable Bowel Syndrome Using α-[11C]methyl-L-tryptophan, Positron Emission Tomography and Statistical Parametric Mapping

BACKGROUND: Irritable bowel syndrome (IBS) is the most common functional bowel disorder and has a strong predominance in women. Recent data suggest that the brain may play an important role in the pathophysiology of IBS in the brain-gut axis. It is strongly suspected that serotonin (5-HT), a neurotransmitter found in the brain and gut, may be related to the pathophysiology of IBS. It is reported that a 5-HT3 antagonist is effective only in female patients with diarrhea-predominant IBS