Effect of dipyridamole on adenine incorporation into hypoxanthine nucleotides of fresh red blood cells.
An investigation was carried out on the penetration of [8-14C]adenine into fresh human red blood cells and of adenine incorporation into hypoxanthine nucleotides of red blood cells incubated in: 1) a medium containing adenosine, pyruvate, inorganic phosphate and NaCl, and 2) APP medium containing 1 X 10(-4) M dipyridamole (APPD medium). It was found that dipyridamole inhibits by about 45% the penetration of adenine into the red blood cells, and by 18% the incorporation of the isotope into the nucleotides of the cells under study. The inhibition of nucleotide synthesis and incorporation of the isotope into them did not apply to IMP, whose content--following erythrocyte incubation in APPD medium--increased 3.5 times, i.e. from 1.52 to 5.30 mumole/g Hb. At the same time there was an increase of the isotope count from 0.12% in IMP isolated from APP incubated erythrocytes to 0.34% in IMP synthesized in APPD incubated erythrocytes. Erythrocyte incubation in APPD medium reduced ITP synthesis by about 53% relative to its synthesis observed after erythrocyte incubation in APP medium equal to 1.40 mumole per g Hb.
D000225:Adenine / Q000097:blood*; D001692:Biological Transport / Q000187:drug effects; D002250:Carbon Radioisotopes; D004176:Dipyridamole / Q000494:pharmacology*; D004912:Erythrocytes / Q000187:drug effects / Q000378:metabolism*; D006801:Humans; D019271:Hypoxanthine; D007042:Hypoxanthines / Q000097:blood; D007291:Inosine Monophosphate / Q000096:biosynthesis / Q000097:blood*; D007292:Inosine Nucleotides / Q000097:blood*
D002250:Carbon Radioisotopes; D007042:Hypoxanthines; D007292:Inosine Nucleotides; D007291:Inosine Monophosphate; D019271:Hypoxanthine; D004176:Dipyridamole; D000225:Adenine