[The effect of thrombin on glycolysis in human thrombocytes]

The experiments were carried out in order to study the mechanism of thrombin--induced stimulation of glycolysis in washed human platelets. The platelets, isolated from human blood and resuspended in Krebs-Ringer-phosphate buffer (pH 7.4), were incubated in water bath (37 degrees C) either without (control) or with thrombin (1 NIH U/ml platelet suspension). Lactate, glycolytic intermediates and adenine nucleotides were measured in the neutralized perchloric acid extracts of platelets by enzymatic analysis and using the fluorimetric methods. The results of this study show that thrombin significantly increases the rate of lactate production in washed human platelets. At the same time thrombin induces the profound changes in the levels of platelet glycolytic intermediates with the "crossover" point at phosphofructokinase step of glycolysis. The results are interpreted as indicating that thrombin stimulates platelet glycolysis through allosteric phosphofructokinase activation due to the changes in adenine nucleotides energy charge.