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A Giacomello

Publications and source records attributed to A Giacomello.

At least 37 records · Page 2Linked to original sources
PubMed1987

Reutilization pathway of purine nucleotides in human erythrocytes.

Human erythrocytes can operate the pyrophosphorolysis of IMP and utilize the phosphoribosyl moiety of this compound for the synthesis of AMP and of GMP from exogenous purine bases. Erythrocyte purine phosphoribosyltransferases seem to have a role in this interconversion pathway.

Adenosine Monophosphate↗
PubMed1985

Hypoxanthine-guanine exchange by intact human erythrocytes.

The uptake and release of [14C]hypoxanthine by human erythrocytes, suspended in a tris(hydroxymethyl)aminomethane (Tris)-glucose-NaCl isotonic medium (pH 7.4), have been studied at 37 degrees C. The uptake of hypoxanthine, mediated by its incorporation into inosine 5'-monophosphate (IMP), was markedly stimulated by preincubating the cells in phosphate-buffered saline. After a lag time, [14C]IMP-enriched erythrocytes released [14C]hypoxanthine in the medium. Formycin B, at concentrations known to inhibit purine nucleoside phosphorylase in intact erythrocytes, affected hypoxanthine uptake and release and led to an increase in the intracellular concentration of inosine, suggesting that the main catabolic path of IMP is the sequential degradation of the nucleotide to inosine and hypoxanthine. The addition of guanine to a suspension of [14C]IMP-enriched erythrocytes led to an increase in the rate of [14C]hypoxanthine release, which was unaffected by the presence of formycin B. During the guanine-induced hypoxanthine release, guanine was taken up by the cells as GMP. These results suggest that the presence of guanine in the incubation medium activates a catabolic path in human erythrocytes leading to IMP degradation without formation of inosine.

Erythrocytes↗