All Phenotypes Tg(Ins1-GAS)1Sbr MGI Mouse

increased incidence of tumors by chemical induction ( J:63579 )

• total number of azoxymethane (AOM)-induced adenocarcinomas per colon is slightly higher than in wild-type, however no mutants died after AOM treatment compared to 20% f wild-type

increased carcinoma incidence ( J:59575 )

• all mice older than 20 months of age exhibit intramucosal dysplasia and most older mice have intramucosal carcinomas

• majority of mice followed up to 20 months of age develop gastric carcinomas that invade the submucosa, muscularis, and vasculature

• however, no evidence of metastases to lymph nodes or other tissues is seen

increased tumor incidence following infection ( J:59575 )

• mice infected with Heliobacter felis at 4 weeks of age exhibit accelerated progression to gastric carcinoma, with 85% developing intramucosal carcinoma, with submucosal invasion in 54% of mice, and intravascular invasion in 46% of mice

increased circulating gastrin level ( J:59575 , J:63579 )

• mice initially show mild hypergastrinemia that develops into moderate hypergastrinemia with age (J:59575)

• blood levels of gastrin are higher than in wild-type (J:63579)

increased incidence of tumors by chemical induction ( J:63579 )

• total number of azoxymethane (AOM)-induced adenocarcinomas per colon is slightly higher than in wild-type, however no mutants died after AOM treatment compared to 20% f wild-type

abnormal intestine morphology ( J:59575 )

• mice exhibit intestinal metaplasia at 20 months of age

abnormal stomach morphology ( J:59575 )

• mice develop foveolar hyperplasia and thickened gastric folds

abnormal gastric gland morphology ( J:59575 )

• small increase in the number of enterochromaffin-like (ECL) cells at 1 month of age

• ECL cell numbers decrease by 12 months of age and show an altered distribution with increasing numbers in the upper half of the gastric glands

• hypertrophy of the oxyntic glands at 20 months of age, caused primarily by foveolar hyperplasia

abnormal gastric parietal cell morphology ( J:59575 )

• increase in the number of parietal cells at 2 and 3 months of age

• parietal cell numbers decrease to less than 68% of normal by 10 months of age and less than 40% of normal by 12 months and only a small number of parietal cells are present at 20 months

increased stomach mucosa thickness ( J:59575 )

• expansion of surface mucous cells in the gastric pit region leading to an overall increase in mucosal thickness

gastric hypertrophy ( J:59575 )

• mice exhibit gastric hypertrophy at 20 months of age; hypertrophy involves only the fundus of the stomach

excessive digestive secretion ( J:59575 )

• mice exhibit a 2-3-fold increase in stimulated gastric acid secretion at 1 and 4 months of age

hypochlorhydria ( J:59575 )

• mice 5 months and older show a decline in the level of stimulated acid secretion, with significantly lower level of acid secretion at 12 months of age and no acid secretion at 20 months of age