Effects of various chemicals including bile acids and chemical carcinogens on the inhibition of metabolic cooperation.

The effects of various chemicals, such as bile acids, a lectin, polyamines and chemical carcinogens, on metabolic cooperation in the hypoxanthine-guanine phosphoribosyl transferase system were surveyed. Among bile acids, lithocholic acid, chenodeoxycholic acid and ursodeoxycholic acid inhibited metabolic cooperation. However, cholic acid, deoxycholic acid and dehydrocholic acid did not. There was a structure-activity relationship among these compounds for the inhibition of metabolic cooperation. The metabolic cooperation was not inhibited by such chemicals as phytohemagglutinin, three polyamines, 7, 12-dimethylbenz [a] anthracene, N-methyl-N'-nitro-N-nitrosoguanidine, 4-nitro-quinolone 1-oxide and three biphenyl compounds. These results should be useful in relation to studies on the mechanism of inhibition of metabolic cooperation and on the relationship between this inhibitory activity and the tumor-promoting activity of various chemicals.