title: Metabolism of guanosine in human erythrocytes.
abstract: The metabolism of guanosine in human erythrocytes has been studied in two different experimental systems--direct incubation and dialysis incubation--the latter allowing continuous addition and removal of substances. Intra- and extracellular purine compounds were analyzed using high-performance liquid chromatography (HPLC). At 37 degrees C, a normal pH (7.4) and a favorably high concentration of inorganic phosphate, guanine nucleotides were synthesized at a substance rate of about 0.17 mmol . h-1 (calculated per liter erythrocytes) when guanosine was kept at a concentration of 25 mumol . l-1. At a higher guanosine concentration the rate of synthesis increased only moderately. Erythrocytes loaded with guanylates lost these nucleotides at a rate of 0.023 mmol . h-1 at a normal phosphate concentration and somewhat slower at a higher phosphate concentration. The metabolism kept the guanylates in an equilibrium that was similar to the equilibrium between the adenylates.
mesh_terms: D001786:Blood Glucose / Q000378:metabolism; D001793:Blood Preservation / Q000379:methods; D003956:Dialysis; D004734:Energy Metabolism; D004912:Erythrocytes / Q000378:metabolism*; D006147:Guanine / Q000097:blood; D006151:Guanosine / Q000097:blood*; D006160:Guanosine Triphosphate / Q000097:blood; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007773:Lactates / Q000097:blood; D013997:Time Factors
chemical_list: D001786:Blood Glucose; D007773:Lactates; D006151:Guanosine; D006147:Guanine; D006160:Guanosine Triphosphate