Induction of gastric tumor and intestinal metaplasia in rats exposed to localized X-irradiation of the gastric region.
The induction of gastric tumor and intestinal metaplasia was examined in 8-week-old male JCL/SD rats exposed to localized X-irradiation of the gastric region. The animals were each given two 20 Gy fractions of X-rays, with a one-week interval between fractions (total, 40 Gy). Nine atypical hyperplasias (20%) and 13 adenocarcinomas (28%) in the pyloric mucosa of the glandular stomach were found in 46 animals with X-irradiation. The incidence of intestinal metaplasia was 93% in the pyloric mucosa, 50% in the fundic mucosa and 96% in both the pyloric and fundic mucosa. Type B metaplasia (intestinal metaplasia without Paneth cells) was most common and type C (intestinal metaplasia with Paneth cells) was less frequent. No gastric tumor or intestinal metaplasia appeared in non-irradiated control rats. This study shows that local X-irradiation of the gastric region induced both gastric tumor and intestinal metaplasia independently.
D000818:Animals; D002294:Carcinoma, Squamous Cell / Q000209:etiology; D004307:Dose-Response Relationship, Radiation; D007414:Intestinal Neoplasms / Q000209:etiology* / Q000473:pathology; D008297:Male; D008679:Metaplasia; D009381:Neoplasms, Radiation-Induced / Q000209:etiology*; D010212:Papilloma / Q000209:etiology; D051381:Rats; D013274:Stomach Neoplasms / Q000209:etiology*; D014965:X-Rays