1974 Volume 26 Issue 2 Pages 140-162
To clarify the relationships between gastric carcinogenesis and nutrition, the following study was undertaken. Part I of this study is concerned with the effect of arginine imbalanced diet on the genesis and growth of carcinoma of the glandular stomach in rats induced by MNNG.
The experimental animals were male rats of Wistar strain.
The diets given to rats were as follows:
1.15% casein diet supplemented with 5% arginine.
2.8% casein diet supplemented with 5% arginine.
3.20% casein diet.
4.13% casein diet.
The last two diets were used as controls. These diets were given isocalorically every day (40.5 Cal/head/day).
The rats received MNNG dissolved in tap water in the concentration of 83γ-/m1 ad libitumfor 40 weeks.
The following results were obtained:
1. These arginine imbalanced diets had no inhibitory effect on normal body growth.
2. A diet of 15%casein supplemented with 5%arginine suppressed significantly both the incidence and growth of carcinoma of the glandular stomach, while an 8% casein diet supplemented with 5%arginine did not reveal any significant effect on carcinogenesis when compared with control group.
3. The serum arginine level and urinary urea excretion were increased significantly in rats fed on arginine supplemented diets.
4. The activities of ornithine tanscarbamylase in the serum, liver and tumor tissues of the rats bearing glandular stomach carcinoma were increased when the rats were fed on arginine supplemented diets, but the activities of aspartate transcarbamylase were comparatively decreased in these rats.
5. From these results, it is considered that the suppressive effect of arginine imbalanced diets on the incidence and growth of carcinoma of the galandular stomach depends mainly on the acceleration of urea cycle metabolism by excess arginine, which may result in the suppression of the flow of carbamylphosphate into the de novosynthetic pathway of pyrimidine nucleotides.
