[Changes of cytoplasmic calcium and magnesium concentration and calcium distribution in human platelets caused by thrombin].

Changes of calcium and magnesium concentration in human platelets during thrombin induced agglutination and the distribution of the respective concentration in the platelet population were measured by fluorescence probe using fura 2, mag-fura 2 and fluo 3. The cytoplasmic free calcium concentration increases with addition 2 thrombin. When the thrombin concentration was increased to 0.5 U/ml, the calcium concentration increase showed two rising peaks. The popular cytoplasmic calcium concentration in platelets shows normal distribution. The cytoplasmic free magnesium concentration also increases with increase of calcium concentration, showing that magnesium also plays a significant effect in the condensation of platelets.