There was no significant difference in somatostatin immunoreactivity intensity between the controls (127.1±0.9) and the IBS-total (124.8±0.5), IBS-D (125.0±0.7), IBS-M (125.6±0.6) and IBS-C (124.3±1.0) patients (P=0.369; Figs. 5 and 6). This evidence concerns the gene SST and irritable bowel syndrome.