Urokinase as a Cell Product
Fibrin deposition occurs in health and disease. The formation of fibrin results from the sequential activation of proteases according to a scheme now well known as the coagulation cascade. A variety of stimuli can initiate this cascade and the resultant fibrin may be involved in physiological (healing) or pathological (vascular obstruction) sequelae. Resolution of fibrin deposits is accomplished by the action of an enzyme system which has as a substrate the insoluble fibrin polymers. This is the fibrinolytic system and, akin to the coagulation system, consists of sequential activation of proenzymes. Plasminogen, a circulatory ß-globulin, is converted to plasmin (fibrinolysin) by tissue or plasma kinases (activators). One of these activators, urokinase, is produced by renal cells and is excreted in the urine. The teleologically inclined will want to consider that this system maintains the urinary tract free from obstructing fibrin clots. Urokinase has been found therapeutically useful, thus stimulating a search for production sources other than human urine. One successful approach is based on cell culture, thus the inclusion of this topic in your program. I should now like to consider with you the therapeutic use of urokinase, the methods of isolation, and some recent data regarding its function.
KeywordsThrombolytic Therapy Human Urine Fetal Kidney Myocardial Infarction Trial Human Fetal Kidney
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- 2.A National Cooperative Study: The Urokinase Pulmonary Embolism Trial Circulation 47: Suppl. 2: 1–108, 1973Google Scholar
- 5.Williams, J.R.B. The fibrinolytic activity of urine. Brit. J. Exp. Pathol. 32: 530–537, 1951.Google Scholar
- 6.Sobel, G.W., Mohled, S.R., Jones N.W., et al. Urokinase: an activator of plasma Profibrinolysin extracted from urine. Am. J. Physiol. 171; 768, 1952.Google Scholar
- 9.Lesuk, A., Terminiello, L., Traver, J.H. Biochemical and Biophysical Studies of Human Urokinase. Thrombosis et Diathesis Haemorrhagica 18: 293–294, 1967.Google Scholar
- 10.Murano, G., et al. Inhibition of high and low molecular weight urokinase by plasma inhibitors. Circulation 58:II-136, 1978.Google Scholar