Purine Release by Human Erythrocytes
The importance of blood and, in particular, of erythrocytes as a vehicle for transport of purines is well known1,2. Considerable quantities of purines enter and leave the nucleotide pools of red cells which take up adenine, guanine, hypoxanthine, and xanthine and convert them into nucleotides. No matter what purine is taken up by erythrocytes, hypoxanthine appears to be the main purine released in vivo. Human erythrocytes cannot synthesize purines de novo and are unable to convert hypoxanthine or guanine into adenine. Hypoxanthine release is mediated by prior conversion of the various purine nucleotides to IMP. In the present paper, some of the mechanisms which regulate the catabolic paths of this nucleotide are studied.
KeywordsHuman Erythrocyte Purine Nucleoside Phosphorylase Steady State Kinetic Preincubation Time Purine Release
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