title: A novel pathway for the production of H2 S by DAO in rat jejunum.
abstract: Hydrogen sulfide (H2 S) is endogenously generated from L-cysteine (L-Cys) by the enzymes cystathionine-β-synthase (CBS) and cystathionine-γ-Lyase (CSE). Hydrogen sulfide is also produced from D-cysteine (D-Cys) by D-Amino acid oxidase (DAO).
  
  
  
  The H2 S production was measured by the methylene blue assay. The expression of DAO was investigated by Western blotting and immunohistochemistry. The short-circuit current (Isc) was recorded using the Ussing chamber technique.
  
  
  
  The epithelium in rat jejunum possesses DAO, and generates H2 S. D-cysteine, originally used as a negative control for L-Cys, significantly increases the H2 S release, which is inhibited by I2CA, an inhibitor of DAO. In vitro study by Ussing chamber technique reveals that D-Cys decreases the Isc across the epithelium of the rat jejunum and enhances the Na(+) -coupled L-alanine transport.
  
  
  
  A novel pathway for the production of H2 S by DAO exists in rat jejunum.
authors.affiliation: Department of Anesthesiology, Qilu Hospital, Shandong University, Jinan, China.
authors.forename: S
authors.initials: S
authors.lastname: Tang
authors.affiliation: Department of Physiology, School of Medicine, Shandong University, Jinan, China.
authors.forename: D
authors.initials: D
authors.lastname: Huang
authors.affiliation: Department of Physiology, School of Medicine, Shandong University, Jinan, China.
authors.forename: N
authors.initials: N
authors.lastname: An
authors.affiliation: Department of Physiology, School of Medicine, Shandong University, Jinan, China.
authors.forename: D
authors.initials: D
authors.lastname: Chen
authors.affiliation: Department of Thoracic Surgery, Shandong Tumor Hospital, Jinan, China.
authors.forename: D
authors.initials: D
authors.lastname: Zhao
mesh_terms: D000818:Animals; D003605:D-Amino-Acid Oxidase / Q000096:biosynthesis*; D006862:Hydrogen Sulfide / Q000378:metabolism*; D007413:Intestinal Mucosa / Q000166:cytology / Q000378:metabolism*; D007583:Jejunum / Q000166:cytology / Q000378:metabolism*; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D015398:Signal Transduction / Q000502:physiology*
chemical_list: C485958:Dao1 protein, mouse; D003605:D-Amino-Acid Oxidase; D006862:Hydrogen Sulfide
keywords: D-Amino acid oxidase; D-cysteine; hydrogen sulfide; jejunum; short-circuit current