[Studies of the effects of low-molecular uremic toxins on anaerobic metabolism of human erythrocytes].

The effect of methylguanidine (MG) and guanidinosuccinic++ acid (GSA) on the anaerobic glycolysis of normal human red blood cells was studied in vitro after three-hours incubation at temperature 37 degrees C. The changes of glucose and lactic acid levels as well as intermediate metabolites and adenine nucleotides of carbohydrate metabolism were determined. Glucose and lactic acid were measured with enzymatic methods, however main phosphate compounds and nucleotide coenzymes were determined by a method of column chromatography. The studies have shown, that GSA in concentrations approximate to those appearing in the plasma patients with chronic renal failure, insignificant enhanced glucose utilization in normal erythrocytes with simultaneous significant decrease produce of lactic acid. Methylguanidine have weakly effected on this process. Subsequent studies have demonstrated that mixture MG (5.4 x 10(-5) mol/dm3) and GSA (2.8 x 10(-5) mol/dm3) induced characteristic changes in composition of main phosphate compounds of carbohydrate metabolism in human red blood cells. The statistically significant decrease of ATP in blood cells with simultaneous increase ADP and AMP were observed. The concentrations of hexose monophosphate, fructose-1,6-diphosphate, triosephosphate, and 2,3-diphosphoglycerinic acid were also higher. The inorganic phosphate concentration was over 80% higher than in control cells. The results of our studies have revealed that energetic metabolism was inhibited in red blood cells which were incubated with MG and GSA.