The effect of guanidinosuccinic acid (GSA) on carbohydrate metabolism in human red blood cells was studied in vitro (t =37C). For this purpose glucose and lactic acid levels as well as carbohydrate intermediates and adenine nucleotides were estimated in erythrocytes incubated with GSA at concentrations 9.0x10-6, 2.7x10-5 or 5.4x10-5 mol/l. Glucose and lactic acid were determined by enzymatic methods and phosphate compounds by the column chromatography. The studies have demonstrated that GSA at concentrations close to those found in the plasma of patients with chronic renal failure stimulated process of glucose utilisation in erythrocytes with simultaneous inhibition of lactate production. Guanidinosuccinic acid (2.7x10-5 mol/l) produced statistically significant decrease of ATP concentration in erythrocytes with simultaneous increase of ADP, AMP, and 2,3-DPG levels. The concentrations of fructose-1,6-diphosphate, triose phosphates and inorganic phosphate were also increased. The demonstrated changes in the composition of the main intermediate compounds of carbohydrate metabolism and adenine nucleotides in erythrocytes incubated with GSA could be related to an inhibition of energy metabolism of red blood cells.

Keywords: Carbohydrate Metabolism, erythrocyte, guanidinosuccinic acid (GSA), Uremia