Certain Nucleotide Relationships in Normal and in Tumor-Bearing Mice ∗

Abstract

Summary

1. Data are presented on the blood nucleotide level of mice in estrus, diestrus, in pregnancy, and after thyroid and thiouracil feeding. Of these conditions, only pregnancy produces a significant lowering of the nucleotide fraction containing AA, ADP, and ATP. This decrease is similar to that observed in mice bearing sarcoma 180. In pregnant mice the blood level begins to return to normal after the 16th day of pregnancy. 2. During tumor growth, as blood nucleotide decreases, tumor nucleotide increases, reaching a maximum at about the 8th day after implantation, followed by a rapid fall. This fall appears to be correlated with the tendency (beginning about the 10th day of tumor growth) for the blood nucleotide level in tumor-bearing mice to return to normal. 3. The intravenous injection of adenylic acid into normal mice causes a transitory rise in blood ATP. With a dose of 4 mg, this increase is in excess of that in the total purine. A similar increase in blood ATP occurs after the injection of AA into the blood stream of tumor-bearing animals. The tumors of such injected animals show a lowered level of AA) ATP, and total purine, but an elevated level of ADP as compared with uninjected controls.