Metabolism of adenine in mice.

Several contradictory reports (24) concerning the degree of lability of the adenine ring in mammals have appeared. Gordon first suggested that complex paths may be involved in incorporation of exogenous purines or in biological interconversions of purines. Incomplete experiments (2) and interpretations of Gordon (5) were questioned in a review by Brown and Roll (6) and were shown to be erroneous at least for ribonucleic acid of rat liver by Abrams (3). A comparison of the incorporation of adenine-2-Cl4 (Ad-2-CY4), adenine4, 6-C14 (Ad-4 ,6-C14), and adenine-8-W (Ad-8-C14) into nucleotide adenine, ribonucleic acid (RNA) adenine and guanine, and deoxyribonucleic acid (DNA) adenine and guanine in five tissues of C57 mice 1 to 28 days after administration is reported here. No evidence was found for extensive ring lability. A decrease of the adenine to guanine (Ad: Gu) specific activity ratio with time has been observed. Other factors affecting adenine utilization and conversion to guanine are discussed.