The role of nNOS-mRNA expression in patients with diarrhea predominant IBS / 中华消化杂志

ABSTRACT

Objective To investigate the possible role of mRNA expression of nitric oxide synthase in the abnormal intestinal motility and visceral perception in patients with diarrhea predominant IBS. Methods Anorectal manometry and rectal visceral sensory thresholds were examined in 25 patients with diarrhea predominant IBS and 15 healthy controls by means of electric barostat and perfusion catheter manometer. The quantity of NO was measured using nitrate/nitrite colorimetric assay. The nerve fibers containing NOS in mucosal muscular layer of colon was quantitatively measured with NADPH diaphorase histochemistry assay and computer image analysis. The expression of neuronal nitric oxide synthase (nNOS) mRNA was determined with fluorescence quantitative polymerase chain reaction (FQ PCR). Results Thresholds of first perception, defecation and pain in patients with IBS were significantly lower than those of controls. The motility indexes of sigmoid and rectum were significantly higher than those of normal controls ( P