Critical Evaluation of the Fibrin Plate Method for Estimating Fibrinolytic Enzymes and Activators

Summary

1. Studies of the fibrinolytic effect of spontaneously activated plasmin preparations on normal and heated bovine fibrin plates showed that human plasmin preparations can be obtained, to which heated fibrin possesses a higher sensitivity than native fibrin.

2. The results suggest that spontaneously activated human plasmin prepared from an euglobulin fraction is more or less accompanied by an agent which acts as activator for bovine plasminogen contained in native fibrin plates. It seems that this agent is identical to a serum factor which acts physiologically as plasminogen activator and is also responsible for the socalled “spontaneous activation”.

3. The findings emphasize the necessity for standardizing testing procedures. Variations in processing the fibrinogen, variations in fibrinogen concentration, and especially in the duration of the heat treatment of the fibrin plates, may cause significant variations in the resulting sensitivity of the method which in turn may be reflected in diverging apparent activities.

• References

• 1 Albrechtsen O. K, Storm O, Classen M. Fibrinolytic Activity in Some Human Body Fluids. Scand. J. clin. Lab. Invest 10: 310 1958;
• 2 Albrechtsen O. K, Thaysen J. H. Fibrinolytic Activity in Human Saliva. Acta physiol. scand. 35: 138 1955;
• 3 Astrup T. Fibrinokinase. Acta physiol. scand. 24: 267 1951;
• 4 Astrup T, Crookston J, Mac Intyre A. Proteolytic Enzymes in Blood. Acta physiol. scand. 21: 238 1950;
• 5 Astrup T, Müllertz S. The Fibrin Plate Method for Estimating Fibrinolytic Activity. Arch. Biochem. 40: 346 1952;
• 6 Astrup T, Sterndorff I. Fibrinolytic Activity of Tissue Extracts and of Trypsin. Nature 170: 981 1952;
• 7 Astrup T, Sterndorff I. An Activator of Plasminogen in Normal Urine. P. S. E. B. M. 81: 675 1952;
• 8 Astrup T, Sterndorff I. A Fibrinolytic System in Human Milk. P. S. E. B. M. 84: 605 1953;
• 9 Doleschel W, Auerswald W. Physiko-chemische Untersuchungen an humaner Urokinase mit besonderer Berücksichtigung ihres Verhaltens gegenüber Adsorbenzien. Wien. 2. inn. Med. 41: 49 1960;
• 10 Doleschel W, Auerswald W. Untersuchungen über die Spontanaktivierung von humanem Plasminogen in Gegenwart hoher Salzkonzentrationen. Medicina experimentalis. (in press).
• 11 Kline D. L. The Purification and Crystallization of Plasminogen (Profibrinolysin). J. biol. Chem. 204: 949 1953;
• 12 Lassen M. Heat Destruction of Plasminogen in the Fibrin plate method. Acta physiol. scand. 27: 371 1952;
• 13 Müllertz S. The Estimation of Plasmin and Trypsin by Means of the Plate Method. Acta physiol. scand. 25: 93 1952;
• 14 Müllertz S. The Plasminogen Activator in Spontaneously Active Human Blood. P. S. E. B. M. 82: 291 1953;
• 15 Olesen E. S. Fibrinolytic Activity Derived from Guinea Pig Serum by Peptone. Acta physiol. scand. 41: 187 1957;
• 16 Permin P. M. Nature. 160: 571 1947;
• 17 Permin P. M. Two Simple Methods of Determining Fibrinolytic Enzymes. Acta physiol. scand. 20: 388 1950;
• 18 Remmertle Mar F, Cohen P. P. Partial Purification and Properties of a Proteolytic Enzyme of Human Serum. J. biol. Chem. 181: 431 1949;
• 19 Storm O. Fibrinolytic Activity in Human Tears. Scand. J. clin. Lab. Invest 07: 55 1955;