title: Mechanism and speed of reactions between haemoglobin and glucose consequences for the measurement of glycosylated haemoglobins in patient material.
abstract: The mechanism of the reactions between haemoglobin and glucose in the erythrocyte was investigated in vitro using 14C-labelled glucose. Reaction speed constants were found for the formation of HbA1c (4.2 . 10(-3) and the formation and degradation of the Schiff Base (9.22 . 10(-4) and 0.435, respectively) for concentrations in mmol/l and time in hours at 37 degrees C. An equilibrium constant of 2.12 . 10(-3) was found for the reversible formation of the Schiff Base. The results were included in a mathematical model with which a number of clinically relevant situations were simulated. From the results the conclusion was drawn that during the measurement of fast haemoglobins, the intermediate Schiff Base causes a variation dependent on the glucose concentration at the moment of blood sampling. The model demonstrates that this disturbance can be eliminated by incubating erythrocytes with physiological saline for 10 h at 37 degrees C.
mesh_terms: D001786:Blood Glucose / Q000378:metabolism*; D004912:Erythrocytes / Q000378:metabolism*; D006442:Glycated Hemoglobin / Q000378:metabolism*; D006454:Hemoglobins / Q000378:metabolism*; D006801:Humans; D007700:Kinetics; D008433:Mathematics; D008954:Models, Biological; D012545:Schiff Bases / Q000097:blood
chemical_list: D001786:Blood Glucose; D006442:Glycated Hemoglobin; D006454:Hemoglobins; D012545:Schiff Bases