title: Expression of angiotensin II type 1 and type 2 receptor mRNAs in the gastric mucosa of Helicobacter pylori-infected Mongolian gerbils.
abstract: BACKGROUND
  The renin-angiotensin system (RAS) plays an important role in normal homeostasis, carcinogenesis-related angiogenesis, and cell proliferation. Helicobacter pylori infection causes infiltration of inflammatory cells into the gastric mucosa and is considered the major cause of gastric cancer. Whether RAS plays a role in H. pylori infection-related gastric diseases remains unclear. We investigated the changes in gastric mucosal angiotensin II type 1 receptor (AT1R) and type 2 receptor (AT2R) mRNA levels throughout the time course of H. pylori infection in Mongolian gerbils.
  
  
  METHODS
  Mongolian gerbils were infected with wild-type H. pylori (for 12 months) or with its isogenic oipA mutant (for 3 months). Gastric mucosal AT1R and AT2R mRNA levels were assessed using real-time reverse transcription-polymerase chain reaction.
  
  
  RESULTS
  The gastric mucosal AT1R mRNA level was significantly associated with the severity of inflammatory cell infiltration into the gastric mucosa that reached maximal levels at 12 months after infection in both the antrum and body. Inflammatory cell infiltration scores and AT1R and AT2R mRNA levels were significantly lower in oipA mutant than wild-type infections. Mucosal AT1R and AT2R mRNA expressions in wild-type H. pylori-infected gerbils with gastric ulcers were significantly higher than in those without ulcers (P < 0.01).
  
  
  CONCLUSIONS
  Gastric mucosal ATR expression gradually increases during the course of H. pylori infection. Up-regulation of the RAS in association with progressive gastric inflammation suggests a potential role of the RAS in gastric carcinogenesis. OipA appears to play a role in AT1R and AT2R expression and the resulting inflammation.
authors.affiliation: Department of Medicine-Gastroenterology, Michael E. DeBakey Veterans Affairs Medical Center and Baylor College of Medicine, Houston, TX, USA.
authors.forename: Mitsushige
authors.initials: M
authors.lastname: Sugimoto
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Ohno
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Yamaoka
mesh_terms: D000818:Animals; D001425:Bacterial Outer Membrane Proteins / Q000378:metabolism; D005753:Gastric Mucosa / Q000382:microbiology / Q000473:pathology; D005849:Gerbillinae; D016481:Helicobacter Infections / Q000382:microbiology / Q000473:pathology*; D016480:Helicobacter pylori / Q000302:isolation & purification; D007249:Inflammation / Q000382:microbiology / Q000473:pathology*; D008297:Male; D012333:RNA, Messenger; D044140:Receptor, Angiotensin, Type 1 / Q000235:genetics*; D044139:Receptor, Angiotensin, Type 2 / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors; D015854:Up-Regulation
chemical_list: D001425:Bacterial Outer Membrane Proteins; C526444:OipA protein, Helicobacter pylori; D012333:RNA, Messenger; D044140:Receptor, Angiotensin, Type 1; D044139:Receptor, Angiotensin, Type 2