Increased tissue-type plasminogen activator activity in orthotopic but not heterotopic liver transplantation: The role of the anhepatic period

Hepatology ◽  
1992 ◽  
Vol 16 (2) ◽  
pp. 404-408 ◽  
Author(s):  
C. Minke Bakker ◽  
Herold J. Metselaar ◽  
Theo N. Groenland ◽  
Maria J. Gomes ◽  
Eduard A. R. Knot ◽  
...  
1993 ◽  
Vol 69 (01) ◽  
pp. 056-059 ◽  
Author(s):  
G Himmelreich ◽  
G Dooijewaard ◽  
P Breinl ◽  
W O Bechstein ◽  
P Neuhaus ◽  
...  

SummaryIn orthotopic liver transplantation (OLT) hyperfibrinolysis seems to be of causative importance for intra- and postoperative bleeding. Although recently hyperfibrinolysis has been successfully reduced by intraoperative aprotinin treatment, small increases of fibrinolysis still remain during OLT. Originally, tissue-type plasminogen activator (t-PA) was considered to be responsible for the increases, but the efficacy of aprotinin which inhibits besides plasmin also kallikrein and urokinase-type plasminogen activator (u-PA) suggested also a role for the intrinsic and contact system-dependent plasminogen activators. We investigated the role of u-PA. From 29 patients undergoing OLT with intraoperative aprotinin infusion arterial blood samples were taken at 7 different time points. The preoperative median values for u-PA antigen (u-PA Ag) and plasmin-activatable single-chain u-PA (scu-PA) levels, which were more than 2-fold above normal (both: p <0.01), decreased slightly during the preanhepatic phase and remained unchanged during the anhepatic phase. With reperfusion of the graft liver the two levels decreased significantly (p = 0.0003 and p = 0.006, respectively) to almost normal values, probably due to clearance by the graft liver. Active two-chain u-PA (tcu-PA) was preoperatively 2-fold above the detection limit, remained stable during the preanhepatic phase and increased 2-fold in the anhepatic phase (p = 0.0018). As expected tcu-PA also relapsed upon reperfusion, but to the preoperatively enhanced level, possibly caused by sustained activation of scu-PA by cathepsin B. t-PA activity levels were at the upper end of the normal range preoperatively, slightly increased during preanhepatic and anhepatic phases and decreased significantly with reperfusion. The increases in tcu-PA and t-PA activities during the anhepatic phase coincided with greatly increased fibrinolysis as demonstrated by thrombelastography, indicating that both u-PA and t-PA are involved in the development of fibrinolysis during OLT.One patient was excluded from statistical evaluations because preoperative u-PA Ag, scu-PA, tcu-PA and t-PA activity levels were much higher than in the other 28 patients. In the investigated group this patient was the only one with diffuse peritonitis intraoperatively and severe bleeding complications postoperatively which made retransplantation mandatory.


1989 ◽  
Vol 3 (4) ◽  
pp. 207-214 ◽  
Author(s):  
M.J. Browne ◽  
C.G. Chapman ◽  
I. Dodd ◽  
B. Reavy ◽  
A.F. Esmail ◽  
...  

2013 ◽  
Vol 25 (1) ◽  
pp. 247
Author(s):  
M. J. Izquierdo-Rico ◽  
M. Moreno-Manrique ◽  
F. A. García-Vázquez ◽  
M. J. Sánchez-Calabuig ◽  
P. Coy

Tissue-type plasminogen activator (tPA) is one of the components of the plasminogen-plasmin (PLG-PLA) system, better known as fibrinolytic system for its role in the blood clot lysis. It has been demonstrated recently that the activation of plasminogen into the protease plasmin during the sperm-oocyte interaction in the pig and cow decreases the percentages of penetration and increases monospermy (Mondéjar et al. 2012). However, in the mouse species, it was showed that PLG-PLA system enhances fertilization (Huarte et al. 1993). Expression of tPA has been described in rat oocytes (Bicsak et al. 1989) and cumulus cells (Ny et al. 1987; O’Connell et al. 1987), but no clear evidence about its expression in mouse, pig, and cow oocytes or cumulus cells is available. We hypothesised that differences in the effect of PLG-PLA system on fertilization results between the species mentioned above could be related to differences in tPA expression. The aim of this study was the detection of mRNA encoding tPA in oocytes and cumulus cells in mouse, pig, and cow by molecular analysis. Total RNA was obtained from oocytes and cumulus cells and cDNA was synthesised with an oligo-dT as primer. These cDNAs were used as template in RT-PCR amplifications using specific primers designed based on the GenBank sequence for Mus musculus, Sus scrofa, and Bos taurus tPA (NM_ 008872, NM_214054, NM_174146, respectively). The results of this study showed a different expression in the 3 studied species. In mouse, amplicon encoding tPA was detected in oocytes and cumulus cells. In cow and pig, tPA transcripts were obtained only in cumulus cells. The relation between the differences in the tPA expression pattern and the role of PLG-PLA system on fertilization remains to be investigated. This study was supported by MICINN (AGL2009-12512-C02-01-02).


1994 ◽  
Vol 9 (4) ◽  
pp. 251-253 ◽  
Author(s):  
A. Ruibal ◽  
A. Alvarez ◽  
B. Fernández Llana ◽  
Ma Fernández Fernández ◽  
Ma C. Roiz ◽  
...  

1994 ◽  
Vol 72 (06) ◽  
pp. 900-905 ◽  
Author(s):  
Harold A R Stringer ◽  
Peter van Swieten ◽  
Anton J G Horrevoets ◽  
Annelies Smilde ◽  
Hans Pannekoek

SummaryWe further investigated the role of the finger (F) and the kringle-2 (K2) domains of tissue-type plasminogen activator (t-PA) in fibrin-stimulated plasminogen activation. To that end, the action of purified (wt) t-PA or of variants lacking F (del.F) or K2 (del.K2) was assessed either in a static, human whole blood clot-lysis system or in whole blood thrombi generated in the “Chandler loop”. In both clot-lysis systems, significant differences were observed for the initiation of thrombolysis with equimolar concentrations of the t-PA variants. A relatively minor “lag phase” occurred in thrombolysis mediated by wt t-PA, whereas a 6.4-fold and 1.6-fold extension is found for del.F and del.K2, respectively. We observed identical lag-times, characteristic for each t-PA variant, in platelet-rich heads and in platelet-poor tails of thrombi. Since plasminogen activator inhibitor 1 (PAI-1) is preferentially retained in the platelet-rich heads, we conclude that the inhibitor does not interfere with the initial stage of thrombolysis but exerts its action in later stages, resulting in a reduction of the rate of clot lysis. A complementation clot-lysis assay was devised to study a potential interplay of del.F and del.K2. Accordingly, clot lysis was determined with combinations of del.F and del.K2 that were inversely varied in relation to equipotent dosage to distinguish between additive, antagonistic or synergistic effects of these variants. The isobole for combinations of del.F and del.K2 shows an independent, additive action of del.F and del.K2 in clot lysis. Under the conditions employed, namely a relatively high concentration of fibrin and Glu-plasminogen and a low concentration of t-PA variant, our data show: i) the crucial role of the F domain and the lack of effect of PAI-1 in initiation of thrombolysis, ii) the lack of importance of the fibrimbinding domains of t-PA and the regulatory role of PAI-1 in advanced stages of thrombolysis.


1984 ◽  
Vol 51 (02) ◽  
pp. 157-164 ◽  
Author(s):  
C Kluft ◽  
F E Preston ◽  
R G Malia ◽  
R M Bertina ◽  
G Wijngaards ◽  
...  

SummaryThe effects of orally-administered stanozolol, 5 mg b. d. on fibrinolysis, coagulation and on various haematological and biochemical parameters have been studied in 16 healthy adults, 8 males and 8 females. Statistically significant enhancement of extrinsic (tissue-type) plasminogen activator activity was detected in all subjects studied. This was associated with significant increases in plasma plasminogen and a concomitant reduction in histidine-rich glycoprotein. There were no changes in plasma urokinase activity. Changes in the coagulation system included significant reduction in plasma fibrinogen and elevation of protein C and anti thrombin III. Changes in plasma lipids included significant reduction of HDL cholesterol associated with an increase in LDL triglycerides. No change occurred in total cholesterol. There were no major differences between the sexes, nor were there serious side effects.The effects of stanozolol on extrinsic (tissue-type) plasminogen activator activity, “free” plasminogen, protein C and antithrombin III, argue strongly in favour of its therapeutic potential.


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