The influence of intestinal metaplasia on development of gastric tumors in wistar rats receiving x-rays and mnng, mnu or dmh

Five-week-old male Wistar:Crj rats received two 10 Gy doses of X-rays to the gastric region at a 3-day interval. Two months thereafter the animals were treated with 100 mg/liter of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) for 4 months in their drinking water, N-methyl-N-nitrosourea (MNU) 2 mg/l ml/weekly/ for a total of 10 times by gastric intubation, or dimethylhydrazine (DMH) 20 mg/kg i.m./weekly/20 times. After 1 year, the animals were sacrificeded. There was thus no direct evidence of a histogenetic link between intestinal metaplasia and gastric carcinogenesis in the present results.