scholarly journals Isoflurane preconditioning inhibits the effects of tissue-type plasminogen activator on brain endothelial cell in an in vitro model of ischemic stroke

2017 ◽  
Vol 14 (5) ◽  
pp. 425-433 ◽  
Author(s):  
So Yeong Cheon ◽  
So Yeon Kim ◽  
Eun Hee Kam ◽  
Jae Hoon Lee ◽  
Jeong Min Kim ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Endothelial Cell ◽  
Plasminogen Activator ◽  
In Vitro Model ◽  
Tissue Type ◽  
Brain Endothelial Cell ◽  
Tissue Type Plasminogen Activator ◽  
Type Plasminogen Activator ◽  
Vitro Model

Sonothrombolysis is effective with recombinant tissue-type plasminogen activator, but not with Abciximab

2009 ◽  
Vol 102 (12) ◽  
pp. 1274-1277 ◽  
Author(s):  
Stefan Ossadnik ◽  
Heiko Hütten ◽  
Günter Seidel ◽  
Jürgen Eggers
Keyword(s):  
Plasminogen Activator ◽  
Venous Blood ◽  
In Vitro Study ◽  
Tissue Type ◽  
Clot Lysis ◽  
Tissue Type Plasminogen Activator ◽  
Type Plasminogen Activator ◽  
The Us ◽  
Vitro Model

SummaryTranscranial “diagnostic” ultrasound (US) has been shown to accelerate thrombolysis related to recombinant tissue-type plasminogen activator (rt-PA). In this in vitro study, we evaluated the potential of US to increase clot dissolution mediated by Abciximab (Abc) compared to rt-PA. The effect of 1.8-MHz pulsed wave (PW) Doppler US on dissolution of whole venous blood clots (WBC) and platelet-rich clots (PRC) treated with Abc and rt-PA was investigated in an in vitro model. Clot dissolution was measured by weight loss. Abc-related WBC dissolution was enhanced by additional US, but the effect was not any more detectable when the US was attenuated by a human temporal bone (US-tb). In PRC there was no additional effect of US on the Abc-related clot lysis. Rt-PA-related clot dissolution was increased by US in WBC and PRC as well, however, US-tb was only effective in WBC. The effect of insonation on WBC dissolution treated with the combination of Abc plus rt-PA was lower compared with those treated with rt-PA. In this in vitro experiment, the additional effect of “diagnostic” US in combination with Abc was only present in WBC and less strong than with rt-PA. The results do not support the use of Abc for sonothrombolysis targeting both, fibrin-rich and platelet-rich clots. In contrast, US when combined with rt-PA increases dissolution in both, WBC and PRC as well.

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

1989 ◽  
Vol 61 (03) ◽  
pp. 497-501 ◽  
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.

In Vitro Stability of a Tissue-Type Plasminogen Activator Mutant, BM 06.022, in Human Plasma

1994 ◽  
Vol 72 (06) ◽  
pp. 906-911 ◽  
Author(s):  
D C Rijken ◽  
E Groeneveld ◽  
M M Barrett-Bergshoeff
Keyword(s):  
Plasminogen Activator ◽  
Half Life ◽  
Polyacrylamide Gel Electrophoresis ◽  
Tissue Type ◽  
Single Chain ◽  
Tissue Type Plasminogen Activator ◽  
Type Plasminogen Activator ◽  
Sds Page ◽  
Chain Form

SummaryBM 06.022 is a non-glycosylated mutant of human tissue-type plasminogen activator (t-PA) comprising only the kringle-2 and proteinase domains. The in vivo half-life of BM 06.022 antigen is 4- to 5-fold longer than that of t-PA antigen. The in vitro half-life of the activity of BM 06.022 at therapeutic concentrations in plasma is shorter than that of t-PA. In this study the inactivation of BM 06.022 in plasma was further investigated.Varying concentrations of BM 06.022 were incubated in plasma for 0-150 min. Activity assays on serial samples showed a dose-dependent decline of BM 06.022 activity with a half-life from 72 min at 0.3 μg/ml to 38 min at 10 μg/ml. SDS-polyacrylamide gel electrophoresis (SDS-PAGE) followed by fibrin autography showed the generation of several BM 06.022-complexes. These complexes could be completely precipitated with antibodies against Cl-inactivator, α2-antiplasmin and α1-antitrypsin.During the incubation of BM 06.022 in plasma, plasmin was generated dose-dependently as revealed by varying degrees of a2-anti-plasmin consumption and fibrinogen degradation. SDS-PAGE and immunoblotting showed that single-chain BM 06.022 was rapidly (i. e. within 45 min) converted into its two-chain form at concentrations of 5 μg/ml BM 06.022 and higher.In conclusion, BM 06.022 at therapeutic concentrations in plasma was inactivated by Cl-inactivator, a2-antiplasmin and a j-antitrypsin. The half-life of the activity decreased at increasing BM 06.022 concentrations, probably as a result of the generation of two-chain BM 06.022 which may be inactivated faster than the single-chain form.

Behaviour and Quantitation of Extrinsic (Tissue-Type) Plasminogen Activator in Human Blood

1983 ◽  
Vol 50 (02) ◽  
pp. 518-523 ◽  
Author(s):  
C Kluft ◽  
A F H Jie ◽  
R A Allen
Keyword(s):  
Plasminogen Activator ◽  
Venous Occlusion ◽  
Tissue Type ◽  
Functional Assay ◽  
Uterine Tissue ◽  
Tissue Type Plasminogen Activator ◽  
Type Plasminogen Activator ◽  
Baseline Values

SummaryFunctional assay of extrinsic (tissue-type) plasminogen activator (EPA) in plasma on fibrin plates was evaluated. Using specific quenching antibodies, we demonstrated the method to be specific for EPA under all conditions tested. Contributions of urokinases and intrinsic activators were excluded. The quantity of EPA in blood samples, as compared with purified uterine tissue activator, shows 1 blood activator unit (BAU) to be comparable to 0.93 ng.The median values for EPA activity for healthy volunteers were: baseline, 1.9 BAU/ml (n = 123); diurnal, 5.5 BAU/ml (n = 12); DDAVP administration, 11.7 BAU/ml (n = 39); exhaustive exercise, 25 BAU/ml (n = 24); venous occlusion (15 min), 35 BAU/ml (n = 61). A large inter-individual variation in EPA activity was found, while individual baseline values tended to be constant for periods of weeks.In vitro in blood EPA activity shows a disappearance of 50% in about 90 min at 37° C; EPA activity in euglobulin fractions is stable for ≤2 hr at 37° C.A rapid decrease in EPA activity occurs in vivo, as noted after extracorporal circulation and exercise stimulation (t½ decay, 2-5 min).

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

1986 ◽  
Vol 56 (01) ◽  
pp. 035-039 ◽  
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.

Abstract 1029: Stromelysin-1 is Critical For Intracranial Bleeding After Tissue-type plasminogen activator Treatment Of Stroke In Mice

Circulation ◽  
2007 ◽  
Vol 116 (suppl_16) ◽  
Author(s):  
Yasuhiro Suzuki ◽  
Nobuo Nagai ◽  
Desire Collen ◽  
Roger Lijnen ◽  
Kazuo Umemura
Keyword(s):  
Ischemic Stroke ◽  
Plasminogen Activator ◽  
Placebo Treatment ◽  
Artery Occlusion ◽  
Intracranial Bleeding ◽  
Tissue Type ◽  
Tissue Type Plasminogen Activator ◽  
Mmp Inhibitor ◽  
Type Plasminogen Activator ◽  
Cerebral Artery Occlusion

Background: Tissue-type plasminogen activator (t-PA) is approved for treatment of ischemic stroke patients, but it may increase the risk of intracranial bleeding (ICB). Matrix metalloproteinases (MMPs), which can be activated through the plasminogen/plasmin system, may contribute to ICB after ischemic stroke. Objectives: To explore the contribution of plasminogen, MMP-3 and MMP-9 to ICB associated with t-PA treatment after ischemic stroke. Methods: Using a thrombotic middle cerebral artery occlusion (MCA-O) model, ICB was studied in mice with genetic deficiencies of plasminogen (Plg −/ − ), stromelysin-1 (MMP-3 −/ − ) or gelatinase B (MMP-9 −/ − ) and their corresponding wild-type (WT) littermates. t-PA (10 mg/kg) or its equivalent volume of solvent was administered intravenously 4 hours after MCA-O. The induction of MMP-3 and MMP-9 was also studied in C57BL/6 WT mice. Results: In MMP-3 +/+ WT mice given solvent, ICB was 4.3 ± 2.9 mm 3 (mean ± SD), which was significantly increased with tPA treatment to 9.7 ± 4.7 mm 3 (P<0.05), whereas ICB in MMP-3 −/ − mice was not altered by t-PA treatment (5.7 ± 2.7 mm 3 , as compared to 5.1 ± 1.8 mm 3 without tPA; n = 7–9 in each group). ICB induced by t-PA was significantly less in Plg −/ − (5.7 ± 3.9 mm 3 ) than in WT mice (8.8 ± 3.2 mm 3 , p<0.05) but ICB by t-PA in MMP-9 −/ − (8.3 ± 2.3 mm 3 ) was comparable with that in WT (8.3 ± 3.1 mm 3 ; n=8 –12 in each group). Administration of the broad-spectrum MMP inhibitor GM6001 after t-PA treatment reduced ICB significantly in MMP-3 +/+ (from 6.4 ± 1.9 mm 3 to 4.1 ± 1.9 mm 3 , p<0.05) but not in MMP-3 −/ − mice (2.2 ± 0.6 mm 3 without versus 2.9 ± 1.5 mm 3 with GM6001; n=6 – 8 in each group). MMP-3 expression was significantly enhanced at the ischemic hemisphere; with placebo treatment, it was expressed only in neurons, whereas it was upregulated in endothelial cells with t-PA treatment. Although MMP-9 expression was also significantly enhanced at the ischemic brain, the amount and the distribution were comparable in mice with and without t-PA treatment. Conclusions: Our data with gene deficient mice suggest that plasminogen and MMP-3 are relatively more important than MMP-9 for the increased ICB induced by t-PA treatment of ischemic stroke.

Abstract TMP19: Intravenous Recombinant Tissue-type Plasminogen Activator Use in Young Adults With Acute Ischemic Stroke

Stroke ◽  
2017 ◽  
Vol 48 (suppl_1) ◽  
Author(s):  
Jodi A Dodds ◽  
Ying Xian ◽  
Shubin Sheng ◽  
Gregg Fonarow ◽  
Ronald A Matsouaka ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Plasminogen Activator ◽  
Older Patients ◽  
Young Patients ◽  
Tissue Type ◽  
Stroke Patients ◽  
Younger Patients ◽  
Tissue Type Plasminogen Activator ◽  
Type Plasminogen Activator

Background: Intravenous recombinant tissue-type plasminogen activator (rt-PA) administration improves outcomes in acute ischemic stroke. However, young patients (<40 years old) presenting with stroke symptoms may experience delays in treatment due to misdiagnosis or a reluctance to treat since they do not fit the profile of a typical stroke patient. Methods: We analyzed data from the large national Get With The Guidelines–Stroke registry for acute ischemic stroke patients hospitalized between January 2009 and September 2015. Multivariable models with generalized estimating equations (GEE) were used to test for differences between younger (age 18-40) and older (age > 40) acute ischemic stroke patients, controlling for patient and hospital characteristics including stroke severity. Results: Of 1,320,965 AIS patients admitted to participating hospitals, 2.3% (30,448) were aged 18-40. Among these patients, 12.5% received rt-PA versus 8.8% of those aged >40 (p<0.001). Of patients arriving within 3.5 hours of symptom onset without contraindications, 68.7% of younger patients received IV rt-PA versus 63.3% of older patients (adjusted OR [aOR] 1.30, 95% CI 1.21 to 1.40), without evidence that age-related differences varied by sex (interaction p-value 0.25). Odds ratios of achieving target door-to-CT times and door-to-needle (DTN) times, and outcomes of rtPA-treated patients, are shown in the Table. Conclusions: Young acute ischemic stroke patients did not receive rt-PA treatment at lower rates than older patients. Outcomes were better and the rate of symptomatic intracranial hemorrhage was lower in the young patients. However, younger patients had significantly longer door-to-CT and DTN times, providing an opportunity to improve the care of these patients.

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