title: Wnt5a expression in the hindgut of fetal rats with chemically induced anorectal malformations--studies in the ETU rat model.
abstract: OBJECTIVE
  Wnt5a is involved in the initiating and patterning morphological adaptations of gut. However, its role remained unknown during terminal hindgut development in the normal and anorectal malformation (ARM) rat embryos. This study was designed to investigate the expression pattern of Wnt5a in the terminal hindgut in ARM rat embryos.
  
  
  METHODS
  Ethylenethiourea-induced ARM model was introduced to investigate the expression pattern of Wnt5a during terminal hindgut development using immunohistochemical staining, reverse transcriptase polymerase chain reaction (RT-PCR), and Western blot analysis.
  
  
  RESULTS
  Immunostaining revealed that Wnt5a expression showed space-dependent changes in the developing terminal hindgut. On embryonic day 17 (E17) in normal embryos, the Wnt5a protein was initially expressed in the mesenchyme of the terminal hindgut. From E18 to 19, the positive staining cells gradually increased. The expression was detected mainly in the circular muscle and myenteric plexus of hindgut. In the ARM embryos, on E17, the Wnt5a protein was also expressed in the hindgut. However, from E18 to 19, the positive staining cells in the middle hindgut gradually increased but in the terminal hindgut decreased. In Western blot and RT-PCR, time-dependent changes of Wnt5a protein and mRNA expression were remarkable during the terminal hindgut development in normal and ARM embryos.
  
  
  CONCLUSIONS
  These data implied that the downregulation of Wnt5a at the time of hindgut neuromuscular development might partly be related to the maldevelopment of terminal hindgut in ARM.
authors.affiliation: Department of Pediatric Surgery, Shengjing Hospital, China Medical University, No. 36 Sanhao Street, Heping District, Shenyang 110004, People's Republic of China.
authors.forename: Huimin
authors.initials: H
authors.lastname: Jia
authors.forename: Qingjiang
authors.initials: Q
authors.lastname: Chen
authors.forename: Tao
authors.initials: T
authors.lastname: Zhang
authors.forename: Yuzuo
authors.initials: Y
authors.lastname: Bai
authors.forename: Zhengwei
authors.initials: Z
authors.lastname: Yuan
authors.forename: Weilin
authors.initials: W
authors.lastname: Wang
mesh_terms: D001003:Anal Canal / Q000002:abnormalities* / Q000196:embryology* / Q000378:metabolism / Q000473:pathology; D000818:Animals; D015153:Blotting, Western; D004195:Disease Models, Animal; D005031:Ethylenethiourea; D005333:Fetus / Q000002:abnormalities* / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D007150:Immunohistochemistry; D051381:Rats; D017208:Rats, Wistar; D012007:Rectum / Q000002:abnormalities* / Q000196:embryology* / Q000378:metabolism / Q000473:pathology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D051153:Wnt Proteins / Q000235:genetics / Q000378:metabolism*; D000071818:Wnt-5a Protein
chemical_list: D051153:Wnt Proteins; D000071818:Wnt-5a Protein; C491837:Wnt5a protein, rat; D005031:Ethylenethiourea