Author/Editor		Šabovič, M; Keber, D
Title		In-vitro sinergism between t-PA and scu-PA depends on clot retraction
Type		članek
Source		Fibrinolysis
Vol. and No.		Letnik 9, št. 2
Publication year		1995
Volume		str. 101-5
Language		eng
Abstract		In the present study the synergism between plasminogen activators was studied in an in vitro clot lysis system with a particular respect to the influence of clot retraction. Whole blood non-retracted and retracted clots, labelled with 125-I fibrinogen, were lysed in plasma to which t-PA, scu-PA, urokinase (UK), combination of t-PA and scu-PA (t-PA/scu-PA, molar ratio 1:1) or combination of t-PA and UK (t-PA/UK, molar ratio 1:1) were aded. The lysis was determined by measurement of 125-I content of plasma after 4 h of lysis. The presence of synergism was analysed by mathematical analysis of dose-response curves. Fifty percent lysis of non-retracted clots was achieved with 5nM, 26nM, 17nM, 8nM and 8nM of t-PA, scu-PA, UK, t-PA/scu-PA and t-PA/UK, respectively: whereas 50 percent lysis of retracted clots required 23nM, 59nM and 14nM of t-PA, scu-PA or t-PA/scu-PA, respectively. The maximal lysis of retracted clots with UK reached only 25 percent; therefore the concentrations producing 25 percent lysis (t-PA 8nM, UK 16nM and t-PA/UK 12nM) were used for analysis of synergism between t-PA and UK. The analysis of results showed clear synergism between t-PA and scu-PA in the lysis of retracted clots but not in the lysis of non-retracted clots. No synergism was found between t-PA and UK. In conclusion, our study has demonstrated that in vitro synergism takes place only within a narrow range of relations between plasminogen that is available for binding to fibrin and fibrin itself.
Descriptors		CLOT RETRACTION FIBRINOLYSIS ALTEPLASE UROKINASE PLASMINOGEN ACTIVATORS DRUG SYNERGISM