title: Down-regulation of hydrogen sulfide biosynthesis accompanies murine interstitial cells of Cajal dysfunction in partial ileal obstruction.
abstract: OBJECTIVE
  To investigate the role of endogenous hydrogen sulfide (H(2)S) in partial obstruction-induced dysfunction of the interstitial cells of Cajal (ICC) in mice ileum.
  
  
  METHODS
  Partial intestinal obstruction was induced surgically in male imprinting control region (ICR) mice. ICC networks were studied by Immunohistochemistry. Electrical activity was recorded by intracellular recording techniques. The expression of ICC phenotype marker c-kit receptor tyrosine kinase (c-kit), membrane binding stem cell factor (mSCF), the endogenous H(2)S biosynthesis enzymes cystathionine-β-synthase (CBS) and cystathionine-γ-lyase (CSE) was studied by Western blotting. The expression of tumor necrosis factor-α (TNF-α) mRNA was observed by using real-time polymerase chain reaction.
  
  
  RESULTS
  Partial intestinal obstruction resulted in ICC networks were disrupted above obstruction 14 days after the operation. The slow waves of intestinal smooth muscles in the dilated region were significantly suppressed and their amplitude and frequency were reduced, whilst the resting membrane potentials were depolarized. The expression of c-kit and mSCF was significantly decreased, also suggesting the disruption of the ICC network. The expression of TNF-α was significantly increased in the tunica muscularis of the obstructed intestine. Treatment of cultured intestinal smooth muscle cells with TNF-α caused dramatic down regulation of mSCF. The expression of CBS and CSE was significantly decreased in the tunica muscularis of the obstructed intestine. Intraperitoneal injection (i.p) of DL-propargylglycine, an irreversible inhibitor of CSE, and aminooxyacetic acid, an inhibitor of CBS, elevated the expression of TNF-α mRNA in the tunica muscularis of the ileum. Obstruction-induced over expression of TNF-α was significantly improved by supplementation of NaHS, but not the expressions of mSCF and c-kit.
  
  
  CONCLUSIONS
  The down regulation of endogenous H(2)S biosynthesis is related to over expression of TNF-α in obstructed small intestine. TNF-α-mediated mSCF down-regulation is not the only reason of partial intestinal obstruction-induced loss of ICC.
authors.affiliation: Department of Physiology, Shanghai Jiaotong University School of Medicine, Shanghai, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Guo
authors.forename: Xu
authors.initials: X
authors.lastname: Huang
authors.forename: Yi-song
authors.initials: YS
authors.lastname: Wu
authors.forename: Dong-hai
authors.initials: DH
authors.lastname: Liu
authors.forename: Hong-li
authors.initials: HL
authors.lastname: Lu
authors.forename: Young-chul
authors.initials: YC
authors.lastname: Kim
authors.forename: Yong-chul
authors.initials: YC
authors.lastname: Kim
authors.forename: Wen-xie
authors.initials: WX
authors.lastname: Xu
mesh_terms: D000818:Animals; D003541:Cystathionine beta-Synthase / Q000096:biosynthesis; D003542:Cystathionine gamma-Lyase / Q000096:biosynthesis; D004594:Electrophysiology / Q000379:methods; D006862:Hydrogen Sulfide / Q000737:chemistry*; D007150:Immunohistochemistry / Q000379:methods; D056885:Interstitial Cells of Cajal / Q000473:pathology / Q000502:physiology*; D007415:Intestinal Obstruction / Q000378:metabolism*; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D032389:Myocytes, Smooth Muscle / Q000166:cytology; D010641:Phenotype; D019009:Proto-Oncogene Proteins c-kit / Q000096:biosynthesis; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D019089:Stem Cell Factor / Q000096:biosynthesis; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
chemical_list: D012333:RNA, Messenger; D019089:Stem Cell Factor; D014409:Tumor Necrosis Factor-alpha; D019009:Proto-Oncogene Proteins c-kit; D003541:Cystathionine beta-Synthase; D003542:Cystathionine gamma-Lyase; D006862:Hydrogen Sulfide