Gastric tumor induction by 1,2-dimethylhydrazine in Wistar rats with intestinal metaplasia caused by X-irradiation.
Five-week-old male Wistar rats were X-irradiated with a total of 20 Gy in 2 equal fractions at a 3-day interval. 1,2-Dimethylhydrazine (DMH) solution was injected i.m. into the back musculature at a dose of 20 mg/kg body weight weekly for 10 weeks, beginning 20 weeks after the final irradiation. Twelve months after the initial carcinogen treatment, tumors in the fundus of the glandular stomach were observed in 5 of 23 animals receiving both X-irradiation and DMH treatment. No tumors of the glandular stomach were observed in the DMH and X-ray alone or nontreatment groups. It is concluded that the presence of intestinal metaplasia may increase sensitivity to the induction of gastric tumors by carcinogens like DMH.
Watanabe
H
H
Department of Environment and Mutation, Research Institute for Radiation Biology and Medicine, Hiroshima. tonko@ipc.hiroshima-u.ac.jp
Uesaka
T
T
Kido
S
S
Ishimura
Y
Y
Shiraki
K
K
Kuramoto
K
K
Hirata
S
S
Shoji
S
S
Katoh
O
O
Fujimoto
N
N
D019813:1,2-Dimethylhydrazine / Q000494:pharmacology*; D000818:Animals; D002273:Carcinogens / Q000494:pharmacology*; D004195:Disease Models, Animal; D005753:Gastric Mucosa / Q000473:pathology; D007413:Intestinal Mucosa / Q000473:pathology / Q000528:radiation effects; D007422:Intestines / Q000473:pathology* / Q000528:radiation effects*; D008297:Male; D008679:Metaplasia; D051381:Rats; D017208:Rats, Wistar; D013274:Stomach Neoplasms / Q000139:chemically induced* / Q000473:pathology; D014965:X-Rays
D002273:Carcinogens; D019813:1,2-Dimethylhydrazine