title: Enterocromaffin-like cell tumor induced by Helicobacter pylori infection in Mongolian gerbils.
abstract: BACKGROUND
  Gastric carcinoids are strongly associated with chronic atrophic gastritis A, and it is suggested that hypergastrinemia plays a critical role in development of gastric carcinoids. Since Helicobacter pylori infection causes hypergastrinemia, it is held that H. pylori infection produces gastric carcinoids. We followed the histological changes of H. pylori-infected stomachs of Mongolian gerbils for a long time.
  
  
  METHODS
  Five-week-old-male Mongolian gerbils were infected with H. pylori ATCC 43504 with cagA gene, expressing vacuolating cytotoxin. Determination of the serum gastrin and histopathological examination of the stomach at 6, 12, 18, and 24 months after H. pylori inoculation was studied and compared with uninfected animals.
  
  
  RESULTS
  In infected animals, the gastric carcinomas appeared 18 and 24 months after infection. Endocrine cell dysplasias and carcinoids with marked atrophic gastritis of the oxyntic mucosa were observed in the infected animals 24 months after H. pylori inoculation. The serum gastrin level in the infected group increased from an average of 86.2 pg/ml at the beginning of the study to an average of 498 pg/ml and 989 pg/ml at 18 and 24 months after infection, respectively. These changes in the serum gastrin levels were significant compared with uninfected controls that showed no changes.
  
  
  CONCLUSIONS
  H. pylori infection caused not only gastric carcinomas but also enterochromaffin-like cell tumors in Mongolian gerbils, due to hypergastrinemia. This model is thought to be useful to study the relationship between hypergastrinemia and gastric carcinoids.
authors.affiliation: Department of General Medicine, Oita Medical University, Hasama-machi, Oita, Japan.
authors.forename: Jiro
authors.initials: J
authors.lastname: Kagawa
authors.forename: Shoji
authors.initials: S
authors.lastname: Honda
authors.forename: Masaaki
authors.initials: M
authors.lastname: Kodama
authors.forename: Ryugo
authors.initials: R
authors.lastname: Sato
authors.forename: Kazunari
authors.initials: K
authors.lastname: Murakami
authors.forename: Toshio
authors.initials: T
authors.lastname: Fujioka
mesh_terms: D000230:Adenocarcinoma / Q000209:etiology* / Q000382:microbiology / Q000473:pathology; D000818:Animals; D002276:Carcinoid Tumor / Q000209:etiology* / Q000382:microbiology / Q000473:pathology; D004195:Disease Models, Animal; D005753:Gastric Mucosa / Q000382:microbiology / Q000473:pathology; D005755:Gastrins / Q000097:blood; D005849:Gerbillinae; D016481:Helicobacter Infections / Q000150:complications* / Q000382:microbiology; D016480:Helicobacter pylori; D008297:Male; D013274:Stomach Neoplasms / Q000209:etiology* / Q000382:microbiology / Q000473:pathology
chemical_list: D005755:Gastrins