[A pilot study of protein fingerprinting in brain-gut interaction model of irritable bowel syndrome.]

Matrix-assisted laser desorption ionization-time of might-mass spectrometry (MALDI-TOF-MS) was utilized to analyze the protein fingerprint in brain-gut interaction of irritable bowel syndrome (IBS) model rats' colon, so as to find the clues for IBS.

Fourteen healthy male adult Wistar rats were selected and divided into a control and a chronic and acute stress (CAS) group. Colon motility, visceral sensation and behavior changes of rats were detected to evaluate the model. MALDI-TOF-MS was used to observe the overall view of protein in colon so as to study whether there are abnormalities of protein levels in IBS.

As compared with those in the control group, the number of fecal pellets [(6.00 +/- 1.69) pellets/1 h vs (1.14 +/- 0.69) pellets/1 h, P < 0.01] and frequency of abdominal contraction induced by colorectal distention (CRD) increased, while the amount of weight gain [(298.88 +/- 18.61) g vs (348.00 +/- 12.44) g, P < 0.01] and consumption of sucrose solutions [(13.63 +/- 1.69) ml/1 h vs (19.00 +/- 3.06) ml/1 h, P < 0.05] decreased in the CAS group (P < 0.05). As far as protein/peptide quality different peak was concerned, CAS rats had 12 different peaks compared with the control rats. The different proteins could be divided into 4 types, which were related to iron secretion, protein synthesis, G protein system and immunity. The protein levels of the model group were higher than those in the control group (P < 0.05).

The CAS rats integrate the major characteristics of IBS such as altered colon motility, higher visceral hypersensitivity and psychiatric disorder and can mimic the brain-gut interaction of IBS partly. The detection of differential proteins provides reference for the pathogenesis and treatment of IBS.