1974 Volume 26 Issue 2 Pages 163-169
In Part I of the present study, it was shown that the arginine imbalanced diet had significant suppressive effects on incidence and growth of MNNG induced carcinoma of the glandular stomach in rats. Part II of the study is concerned with the mode of action of the arginine imbalanced diet on carcinogenesis of the glandular stomach in rats.
The process of carcinogenesis can be divided into two phases, the initiating and promoting phase. An attempt was made to determine at what phase of the neoplastic process arginine added casein diet might be considered to have its effects.
The animals, the diets and the way of administering MNNG were the same as described in Part I. At the 26th week after the administration of MNNG, the feedings of the arginine supplemented diets and control diets were switched.
The following results were obtained:
1. The diet of 15% casein supplemented with 5% arginine showed a significant suppressive effect on carcinogenesis in the promoting stage and a tendency to suppress slightly in the initiating stage.
2. The diet of 8% casein supplemented with 5% arginine showed a tendency to suppress the carcinogenesis in both the initiating and promoting stages.
3. From these results, it has been recognized that the suppressive effects of excess arginine on carcinogenesis appear in both the initiating and promoting stages.
Therefore, it may be suggested that these effects of arginine imbalanced diets on carcinogenesis may depend not only on the influence of the acceleration of urea cycle metabolism, but also on influences to other metabolic systems.
