Enterochromaffin-like cell carcinoids of gastric mucosa in rats after life-long inhibition of gastric secretion

Digestion. 1986;35 Suppl 1:42-55. doi: 10.1159/000199381.


Small intramucosal tumours in the oxyntic area of the rat stomach were observed in an oncogenicity study with omeprazole. The tumours could be defined as carcinoids of enterochromaffin-like (ECL) cell origin. ECL cells occur exclusively in oxyntic mucosa and respond to the trophic hormone gastrin with a proliferation that becomes exaggerated in old rats. Inhibition of gastric acid secretion is known to induce hypergastrinaemia in rats. According to the common concept of endocrine cells, a sustained hormonal stimulation with gastrin may induce a continuous gradient between hyperplasia and neoplasia of the ECL cells. The tumours found are thus to be regarded as hormone-induced endocrine tumours of the ECL cells in the stomach. The ECL-cell tumours of the rats in the oncogenicity study appeared to belong to the low-malignancy type of carcinoids and did not make their appearance until the end-life period of the study. The sex and species differences observed may be explained by inherent differences in gastrin response, spontaneous ECL cell density or in responsiveness to gastrin-stimulated ECL cell proliferation between sexes and species.

MeSH terms

  • Animals
  • Carcinoid Tumor / pathology*
  • Chromaffin System / pathology*
  • Enterochromaffin Cells / pathology*
  • Female
  • Gastric Mucosa / metabolism
  • Gastric Mucosa / pathology*
  • Gastrins / blood
  • Male
  • Mice
  • Microscopy, Electron
  • Omeprazole
  • Rats
  • Rats, Inbred Strains
  • Sex Characteristics
  • Species Specificity
  • Stomach Neoplasms / pathology*


  • Gastrins
  • Omeprazole