title: The role of the 5-hydroxytryptamine pathway in reflux-induced esophageal mucosal injury in rats.
abstract: BACKGROUND
  Dysfunction of the 5-hydroxytryptamine (5-HT) signaling pathway can lead to gastrointestinal motility and secretion abnormalities and to visceral hypersensitivity. The aim of this study is to investigate the role of 5-HT in reflux-induced esophageal mucosal injury.
  
  
  METHODS
  Fifty 8-week-old male Sprague-Dawley (SD) rats were randomly divided into a gastroesophageal reflux (GER) model group (30 rats) and a sham surgery control group (20 rats). Four weeks after surgery, the esophageal mucosa was collected for histological evaluation, 5-HT concentrations, and 5-HT selective reuptake transporter (SERT) mRNA and 5-HT4 receptor (5-HT4R) protein expressions.
  
  
  RESULTS
  Twenty-seven rats in the GER model group survived, and three rats died. Histologically, in the GER model group, 20 rats had reflux esophagitis (RE group), and 7 rats had non-erosive reflux disease (NERD group). The 5-HT levels in the esophageal tissue from the RE group were significantly higher than those from the control and NERD groups. Both the RE and NERD groups showed significant increases in SERT mRNA expression of the esophageal mucosa than that of the controls, and the SERT mRNA level in the RE group was significantly higher than that in the NERD group. The 5-HT4R protein level of the esophageal mucosa in the RE group was significantly lower than that in the controls and the NERD group.
  
  
  CONCLUSIONS
  We conclude that a 5-HT signaling pathway disorder could be a major factor in the pathogenesis of GER and RE.
authors.affiliation: Department of Gastroenterology, Children's Hospital, Zhejiang University School of Medicine, Hangzhou, 310003, People's Republic of China.
authors.forename: Lingrong
authors.initials: L
authors.lastname: Yang
authors.forename: Haifang
authors.initials: H
authors.lastname: Cai
authors.forename: Jinfa
authors.initials: J
authors.lastname: Tou
authors.forename: Weizhong
authors.initials: W
authors.lastname: Gu
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Shu
authors.forename: Ting
authors.initials: T
authors.lastname: Zhang
authors.forename: Xi
authors.initials: X
authors.lastname: Yang
authors.forename: Zheng
authors.initials: Z
authors.lastname: Shen
authors.forename: Mizu
authors.initials: M
authors.lastname: Jiang
mesh_terms: D000818:Animals; D015153:Blotting, Western; D004942:Esophagitis, Peptic / Q000150:complications / Q000378:metabolism / Q000473:pathology*; D004947:Esophagus / Q000293:injuries / Q000378:metabolism*; D005764:Gastroesophageal Reflux / Q000150:complications / Q000378:metabolism / Q000473:pathology*; D006863:Hydrogen-Ion Concentration; D008297:Male; D009092:Mucous Membrane / Q000293:injuries / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D060888:Real-Time Polymerase Chain Reaction; D044422:Receptors, Serotonin, 5-HT4 / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012701:Serotonin / Q000378:metabolism*
chemical_list: D012333:RNA, Messenger; D016601:RNA-Binding Proteins; C482440:Sert1 protein, rat; D044422:Receptors, Serotonin, 5-HT4; D012701:Serotonin