TEMPERATURE-DEPENDENT FIBRINOLYSIS WITH S TREPTOKINASE

In an in-vitro study standardized test thrombi were incubated at diffe rent temperatures between 25-degrees and 43-degrees-C in a constant te st mixture in which all reagents necessary for fibrinolysis including streptokinase were contained in excess. At each temperature step the d ilution of the standard streptokinase solution (1 : 1000 IU/ml) was me asured at which the test thrombus dissolved in exactly 15 min (clot ly sis test). The highest fibrinolysis activity (dilution of 1 : 1140 of the standard) was obtained at 40-degrees-C, lower activities having be en recorded at both higher and lower temperatures (43-degrees-C: 1 : 1 000; 37-degrees-C: 1 : 900; 34-degrees-C: 1 : 550; 30-degrees-C: 1 : 2 55; 25-degrees-C: 1 : 90). Related to the optimal temperature of 40-de grees-C (100%), the fibrinolytic activity at 25-degrees-C was only 7.9 %. In view of the axial temperature gradients existing in the limbs, the internal temperature in their peripheral parts lies well below the optimal temperature for fibrinolysis. This situation should be taken into account during fibrinolysis procedures for thrombotic occlusions in the limbs.