Enhanced induction of gastric carcinogenesis by N-methyl-N'-nitro-N-nitrosoguanidine in Wistar rats fed a low-protein diet.
The effects of ad libitum feeding of synthetic, low-protein diets on the incidence and number of gastric cancers induced by N-methyl-N'-nitro-N-nitrosoguanidine were investigated in Wistar rats. Rats were fed synthetic diets of equal calorie content containing 25% casein (normal protein diet), 10% casein (low-protein diet), or 5% casein (very-low-protein diet) after treatment with N-methyl-N'-nitro-N-nitrosoguanidine p.o. for 25 weeks. Administration p.o. of a very-low-protein diet containing 5% casein resulted in a significant increase in the incidence and number of gastric cancers in experimental Week 52. However, it did not affect the histology of the cancers. The very-low-protein diet also caused a significant increase in tissue norepinephrine concentration of the antral portion of the gastric wall and in the labeling index of the antral epithelial cells. These findings indicate that a very-low-protein diet enhances gastric carcinogenesis and that this effect may be related to its effect in increasing norepinephrine in the gastric wall and stimulating proliferation of antral epithelial cells.
Tatsuta
M
M
Department of Gastrointestinal Oncology Center for Adult Diseases, Osaka, Japan.
Iishi
H
H
Baba
M
M
Uehara
H
H
Nakaizumi
A
A
Taniguchi
H
H
D000818:Animals; D002455:Cell Division; D004044:Dietary Proteins / Q000378:metabolism*; D005753:Gastric Mucosa / Q000378:metabolism / Q000473:pathology; D008297:Male; D008769:Methylnitronitrosoguanidine / Q000633:toxicity*; D009638:Norepinephrine / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D013274:Stomach Neoplasms / Q000139:chemically induced* / Q000473:pathology; D013564:Sympathetic Nervous System / Q000502:physiology
D004044:Dietary Proteins; D008769:Methylnitronitrosoguanidine; D009638:Norepinephrine