89. Polymorphism of the blood clot lysis enzyme tissue-type plasminogen activator is associated with myocardial infarction

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).

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Requirement of heparin for arterial and venous thrombolysis with recombinant tissue-type plasminogen activator

Blood ◽

10.1182/blood.v77.5.1020.1020 ◽

1991 ◽

Vol 77 (5) ◽

pp. 1020-1024 ◽

Cited By ~ 24

Author(s):

HJ Rapold ◽

HR Lu ◽

ZM Wu ◽

H Nijs ◽

D Collen

Keyword(s):

Plasminogen Activator ◽

Blood Clot ◽

Tissue Type ◽

Clot Lysis ◽

Early Reperfusion ◽

Tissue Type Plasminogen Activator ◽

Group I ◽

Type Plasminogen Activator ◽

Group Ii ◽

Prospective Study Design

Abstract The effect of concomitant intravenous (IV) heparin (200 U/kg bolus, followed by 100 U/kg/h) on the efficacy of arterial and venous thrombolysis with IV recombinant tissue-type plasminogen activator (rt- PA; 0.5 mg/kg over 1 hour) was investigated in a combined femoral arterial and venous thrombosis model in the dog. The arterial model consisted of a high-grade stenosis, endothelial damage, and a thrombotic occlusion, and the venous model consisted of a 125I-fibrin- labeled blood clot. After a dose-finding pilot study in four dogs, a randomized, prospective, and blind study was performed in 20 animals pretreated with 2.8 mg/kg IV acetyl salicylic acid (ASA). The combination of rt-PA and heparin (group I, n = 10) induced early (less than 30 minutes) arterial reperfusion in seven dogs, late (greater than 30 minutes) reflow in two dogs, and persistent occlusion in one dog. rt- PA alone (group II, n = 10) was associated with early reperfusion in one dog, late reflow in three dogs, and persistent occlusion in six dogs (P = .018). Reocclusion occurred in five of nine reperfused dogs of group I and in one of four reperfused dogs of group II (P = not significant). Venous clot lysis amounted to 81% +/- 4% (mean +/- SEM) for group I and to 49% +/- 7% for group II (P less than .001). Template bleeding times increased moderately, but significantly, in group I (from 2.2 +/- 0.2 minutes at baseline to 7.0 +/- 1.4 minutes at 30 minutes, P = .006), but only marginally in group II (from 2.2 +/- 0.2 minutes to 3.6 +/- 0.7 minutes, P = .09). No systemic fibrinogen depletion was observed. Thus, the concommitant use of heparin with rt- PA accelerates arterial reperfusion and enhances venous thrombolysis in dogs pretreated with ASA. These results, obtained in a randomized prospective study design, add to a growing body of experimental and clinical evidence, indicating that thrombolytic therapy with rt-PA requires concomitant adjunctive IV heparin for optimal efficacy, even in the face of treatment with ASA.

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Systemic Hematologic Status Following Intraventricular Recombinant Tissue-Type Plasminogen Activator for Intraventricular Hemorrhage

Stroke ◽

10.1161/strokeaha.111.625749 ◽

2011 ◽

Vol 42 (12) ◽

pp. 3631-3633 ◽

Cited By ~ 11

Author(s):

Daniel B. Herrick ◽

Wendy C. Ziai ◽

Carol B. Thompson ◽

Karen Lane ◽

Nichol A. McBee ◽

...

Keyword(s):

Plasminogen Activator ◽

Intraventricular Hemorrhage ◽

Blood Clot ◽

Laboratory Data ◽

Tissue Type ◽

Clot Lysis ◽

Thrombosis Prophylaxis ◽

Tissue Type Plasminogen Activator ◽

Coagulation Parameters ◽

Type Plasminogen Activator

Background and Purpose— This is the first prospective evaluation of changes in systemic hematologic status following administration of intraventricular recombinant tissue-type plasminogen activator in patients with intraventricular hemorrhage (IVH). Methods— Laboratory data from subjects enrolled onto the Clot Lysis: Evaluating Accelerated Resolution of IVH (CLEAR IVH) Trials were analyzed. We analyzed pre- and post- recombinant tissue-type plasminogen activator dosing coagulation parameters. Longer-term changes in hematologic status were studied in subjects who received the study agent after blood clot in the third/fourth ventricles had resolved radiologically. Results— Plasma fibrinogen increased significantly in both treatment groups. Dosing did not have a significant impact on any systemic coagulation parameters in either treatment group. Conclusions— Intraventricular recombinant tissue-type plasminogen activator is unlikely to impact systemic coagulation or to compound the effects of systemic anticoagulation for deep venous thrombosis prophylaxis. Clinical Trial Registration— URL: http://clinicaltrials.gov . Unique identifier: NCT00650858.

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Requirement of heparin for arterial and venous thrombolysis with recombinant tissue-type plasminogen activator

Blood ◽

10.1182/blood.v77.5.1020.bloodjournal7751020 ◽

1991 ◽

Vol 77 (5) ◽

pp. 1020-1024

Author(s):

HJ Rapold ◽

HR Lu ◽

ZM Wu ◽

H Nijs ◽

D Collen

Keyword(s):

Plasminogen Activator ◽

Blood Clot ◽

Tissue Type ◽

Clot Lysis ◽

Early Reperfusion ◽

Tissue Type Plasminogen Activator ◽

Group I ◽

Type Plasminogen Activator ◽

Group Ii ◽

Prospective Study Design

The effect of concomitant intravenous (IV) heparin (200 U/kg bolus, followed by 100 U/kg/h) on the efficacy of arterial and venous thrombolysis with IV recombinant tissue-type plasminogen activator (rt- PA; 0.5 mg/kg over 1 hour) was investigated in a combined femoral arterial and venous thrombosis model in the dog. The arterial model consisted of a high-grade stenosis, endothelial damage, and a thrombotic occlusion, and the venous model consisted of a 125I-fibrin- labeled blood clot. After a dose-finding pilot study in four dogs, a randomized, prospective, and blind study was performed in 20 animals pretreated with 2.8 mg/kg IV acetyl salicylic acid (ASA). The combination of rt-PA and heparin (group I, n = 10) induced early (less than 30 minutes) arterial reperfusion in seven dogs, late (greater than 30 minutes) reflow in two dogs, and persistent occlusion in one dog. rt- PA alone (group II, n = 10) was associated with early reperfusion in one dog, late reflow in three dogs, and persistent occlusion in six dogs (P = .018). Reocclusion occurred in five of nine reperfused dogs of group I and in one of four reperfused dogs of group II (P = not significant). Venous clot lysis amounted to 81% +/- 4% (mean +/- SEM) for group I and to 49% +/- 7% for group II (P less than .001). Template bleeding times increased moderately, but significantly, in group I (from 2.2 +/- 0.2 minutes at baseline to 7.0 +/- 1.4 minutes at 30 minutes, P = .006), but only marginally in group II (from 2.2 +/- 0.2 minutes to 3.6 +/- 0.7 minutes, P = .09). No systemic fibrinogen depletion was observed. Thus, the concommitant use of heparin with rt- PA accelerates arterial reperfusion and enhances venous thrombolysis in dogs pretreated with ASA. These results, obtained in a randomized prospective study design, add to a growing body of experimental and clinical evidence, indicating that thrombolytic therapy with rt-PA requires concomitant adjunctive IV heparin for optimal efficacy, even in the face of treatment with ASA.

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Mice release less tissue-type plasminogen activator (t-PA) and have more active clot stabilization by FXIII compared to rats which might explain their low rate of blood clot lysis

Fibrinolysis and Proteolysis ◽

10.1016/0268-9499(94)90025-6 ◽

1994 ◽

Vol 8 (1) ◽

pp. 1-8 ◽

Cited By ~ 4

Author(s):

J.J.J. van Giezen ◽

B.N. Bouma ◽

J.W.C.M. Jansen

Keyword(s):

Plasminogen Activator ◽

Blood Clot ◽

Tissue Type ◽

Clot Lysis ◽

Tissue Type Plasminogen Activator ◽

Type Plasminogen Activator ◽

Low Rate

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Recombinant Variants of Tissue-Type Plasminogen Activator Containing Amino Acid Substitutions in the Finger Domain

Thrombosis and Haemostasis ◽

10.1055/s-0038-1646342 ◽

1992 ◽

Vol 68 (06) ◽

pp. 672-677 ◽

Cited By ~ 4

Author(s):

Hitoshi Yahara ◽

Keiji Matsumoto ◽

Hiroyuki Maruyama ◽

Tetsuya Nagaoka ◽

Yasuhiro Ikenaka ◽

...

Keyword(s):

Amino Acid ◽

Plasminogen Activator ◽

Half Life ◽

Tissue Type ◽

Clot Lysis ◽

Amino Acid Substitutions ◽

Wild Type ◽

Plasma Clot ◽

Tissue Type Plasminogen Activator ◽

Type Plasminogen Activator

SummaryTissue-type plasminogen activator (t-PA) is a fibrin-specific agent which has been used to treat acute myocardial infarction. In an attempt to clarify the determinants for its rapid clearance in vivo and high affinity for fibrin clots, we produced five variants containing amino acid substitutions in the finger domain, at amino acid residues 7–9, 10–14, 15–19, 28–33, and 37–42. All the variants had a prolonged half-life and a decreased affinity for fibrin of various degrees. The 37–42 variant demonstrated about a 6-fold longer half-life with a lower affinity for fibrin. Human plasma clot lysis assay estimated the fibrinolytic activity of the 37–42 variant to be 1.4-fold less effective than that of the wild-type rt-PA. In a rabbit jugular vein clot lysis model, doses of 1.0 and 0.15 mg/kg were required for about 70% lysis in the wild-type and 37–42 variant, respectively. Fibrinogen was degraded only when the wild-type rt-PA was administered at a dose of 1.0 mg/kg. These findings suggest that the 37–42 variant can be employed at a lower dosage and that it is a more fibrin-specific thrombolytic agent than the wild-type rt-PA.

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Pharmacokinetics and Haemostatic Status During Consecutive Infusions of Recom binant Tissue-Type Plasminogen Activator in Patients with Acute Myocardial Infarction

Thrombosis and Haemostasis ◽

10.1055/s-0038-1646622 ◽

1989 ◽

Vol 61 (03) ◽

pp. 497-501 ◽

Cited By ~ 47

Author(s):

E Seifried ◽

P Tanswell ◽

D Ellbrück ◽

W Haerer ◽

A Schmidt

Keyword(s):

Myocardial Infarction ◽

Acute Myocardial Infarction ◽

Plasminogen Activator ◽

Peak Plasma ◽

Peak Plasma Concentration ◽

Tissue Type ◽

Tissue Type Plasminogen Activator ◽

Precise Control ◽

Type Plasminogen Activator

SummaryPharmacokinetics and systemic effects of recombinant tissue type plasminogen activator (rt-PA) were determined during coronary thrombolysis in 12 acute myocardial infarction patients using a consecutive intravenous infusion regimen. Ten mg rt-PA were infused in 2 minutes resulting in a peak plasma concentration (mean ±SD) of 3310±950 ng/ml, followed by 50 mg in 1 h and 30 mg in 1.5 h yielding steady state plasma levels of. 2210±470 nglml and 930±200 ng/ml, respectively. All patients received intravenous heparin. Total clearance of rt-PA was 380±74 ml/min, t,½α was 3.6±0.9 min and t,½β was 16±5.4 min.After 90 min, in plasma samples containing anti-rt-PA-IgG to inhibit in vitro effects, fibrinogen was decreased to 54%, plasminogen to 52%, α2-antiplasmin to 25%, α2-macroglobulin to 90% and antithrombin III to 85% of initial values. Coagulation times were prolonged and fibrin D-dimer concentrations increased from 0.40 to 2.7 μg/ml. It is concluded that pharmacokinetics of rt-PA show low interpatient variability and that its short mean residence time in plasma allows precise control of therapy. Apart from its moderate effect on the haemostatic system, rt-PA appears to lyse a fibrin pool in addition to the coronary thrombus.

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G4120, an Arg-Gly-Asp Containing Pentapeptide, Enhances Arterial Eversion Graft Recanalization with Recombinant Tissue-Type Plasminogen Activator in Dogs

Thrombosis and Haemostasis ◽

10.1055/s-0038-1648523 ◽

1992 ◽

Vol 67 (06) ◽

pp. 686-691 ◽

Cited By ~ 12

Author(s):

Hua Rong Lu ◽

Herman K Gold ◽

Zaomin Wu ◽

Tsunehiro Yasuda ◽

Patrick Pauwels ◽

...

Keyword(s):

Plasminogen Activator ◽

Arterial Occlusion ◽

Tissue Type ◽

Clot Lysis ◽

Arterial Graft ◽

Tissue Type Plasminogen Activator ◽

Group I ◽

Type Plasminogen Activator ◽

Platelet Receptor ◽

Observation Period

SummaryThe effects of G4120, a cyclic Arg-Gly-Asp (RGD) containing peptide which inhibits fibrinogen binding to the platelet receptor GPIIb/IIIa, on thrombolysis with recombinant tissue-type plasminogen activator (rt-PA) were investigated in a combined arterial and venous thrombosis model in heparinized dogs. The arterial thrombus model consisted of a 3 cm everted (inside-out) carotid arterial segment inserted into a transsected femoral artery which occludes within 30 min with platelet-rich material and which is resistant to recanalization with 0.5 mg/kg rt-PA. The venous thrombus was a 125I-fibrin labeled whole blood clot produced in the contralateral femoral vein.In 5 dogs given an intravenous bolus of 0.05 mg/kg G4120 followed by a continuous infusion of 0.05 mg/kg per hour for 3 h (group I), arterial occlusion persisted throughout a 4 h observation period and was still present at 24 h in all dogs; the extent of venous clot lysis after 120 min was 27 ± 7%. In 5 dogs given the same infusion of G4120 in combination with 0.5 mg/kg rt-PA over 60 min, recanalization of the arterial graft occurred in all dogs, within 13 ± 2 min and persisted throughout the observation period of 4 h (p = 0.01 versus G4120 or rt-PA alone); at 24 h, however, all grafts were occluded. Venous clot lysis in this group was 75 ± 8% (p = 0.002 versus G4120 alone andp NS versus rt-PA alone). Pathologic analysis revealed platelet-rich or mixed thrombus with platelet-rich and erythrocyte-rich zones. The last 6 dogs were given a reduced dose of G4120 consisting either of a 0.05 mg/kg bolus followed by an infusion of 0.05 mg/kg over 1 h in 3 dogs (group III) or of a single 0.05 mg/kg bolus in 3 dogs (group IV), both given in combination with 0.5 mg/kg rt-PA infused over 60 min. These protocols produced recanalization within 15 ± 2 and 34 ± 8 min, respectively, which was maintained throughout the 4 h observation period. Venous lysis in these groups was 63 ± 4 and 97 ± 1% respectively. Bleeding times prolonged from 1 to 2 min to >30 min with G4120, but returned towards baseline within 2 h after the end of the infusion. Platelet aggregation with ADP was completely inhibited with G4120 but partially recovered within 1 h after the end of the infusion. No fibrinogen breakdown was observed in association with the rt-PA infusion.Thus, G4120, a synthetic GPIIb/IIIa receptor antagonist, enhances and accelerates lysis of platelet-rich arterial thrombosis with rt-PA and prevents reocclusion during and within 3 h after the infusion. It may be useful for the conjunctive use with thrombolytic agents in patients with arterial thromboembolic disease.

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Absence of Synergism Between Tissue-Type Plasminogen Activator (t-PA), Single-Chain UrokinaseType Plasminogen Activator (scu-PA) and Urokinase on Clot Lysis in a Plasma Milieu In Vitro

Thrombosis and Haemostasis ◽

10.1055/s-0038-1661598 ◽

1986 ◽

Vol 56 (01) ◽

pp. 035-039 ◽

Cited By ~ 42

Author(s):

D Collen ◽

F De Cock ◽

E Demarsin ◽

H R Lijnen ◽

D C Stump

Keyword(s):

Human Plasma ◽

Plasminogen Activator ◽

Dose Response ◽

Fibrinolytic System ◽

Tissue Type ◽

Clot Lysis ◽

Single Chain ◽

Tissue Type Plasminogen Activator ◽

Type Plasminogen Activator

SummaryA potential synergic effect of tissue-type plasminogen activator (t-PA), single-chain urokinase-type plasminogen activator (scuPA) or urokinase on clot lysis was investigated in a whole human plasma system in vitro. The system consisted of a human plasma clot labeled with 125I-fibrinogen, immersed in titrated whole human plasma, to which the thrombolytic agents were added. Clot lysis was quantitated by measurement of released 125I, and activation of the fibrinolytic system in the surrounding plasma by measurements of fibrinogen and α2-antiplasmin.t-PA, scu-PA and urokinase induced a dose-dependent and time-dependent clot lysis; 50 percent lysis after 2 h was obtained with 5 nM t-PA, 20 nM scu-PA and 12 nM urokinase. At these concentrations no significant activation of the fibrinolytic system in the plasma was observed with t-PA and scu-PA, whereas urokinase caused significant α2-antiplasmin consumption and concomitant fibrinogen degradation. The shape of the dose-response curves was different; t-PA and urokinase showed a log linear dose-response whereas that of scu-PA was sigmoidal.

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