Lalanne M, Lafleur F
Can J Biochem. 1980 Aug;58(8):607-13. doi: 10.1139/o80-083.
In the presence of allopurinol, apparent phosphoribosylpyrophosphate (PP-ribose-P) availability as measured by adenine incorporation into ribonucleotides was decreased in rat liver cells, hypoxanthine incorporation into ribonucleotides was increased, and there was a large synthesis of inosine from hypoxanthine. Inosine was formed directly by the reversal of the purine nucleoside phosphorylase reaction which was very rapid in liver cells. We tested the hypothesis that utilization of ribose 1-phosphate for inosine synthesis could decrease PP-ribose-P availability. Our results indicate that the apparent decrease of PP-ribose-P availability in the presence of allopurinol was due to competition between adenine and hypoxanthine salvage pathways into nucleotides, and not to the synthesis of inosine.
在存在别嘌呤醇的情况下，通过腺嘌呤掺入核糖核苷酸来衡量，大鼠肝细胞中表观磷酸核糖焦磷酸（PP-核糖-P）的可用性降低，次黄嘌呤掺入核糖核苷酸增加，并且次黄嘌呤大量合成肌苷。肌苷是由嘌呤核苷磷酸化酶反应的逆转直接形成的，该反应在肝细胞中非常迅速。我们检验了核糖-1-磷酸用于肌苷合成会降低PP-核糖-P可用性的假设。我们的结果表明，在别嘌呤醇存在下PP-核糖-P可用性的明显降低是由于腺嘌呤和次黄嘌呤补救途径进入核苷酸之间的竞争，而不是由于肌苷的合成。
