295 RELATIONSHIP BETWEEN PLASMINOGEN ACTIVATOR/PLASMIN SYSTEM AND IN VITRO FERTILIZATION ABILITY IN THE PIG

2006 ◽  
Vol 18 (2) ◽  
pp. 255
Author(s):  
S.-J. Sa ◽  
H.-T. Cheong ◽  
B.-K. Yang ◽  
C.-K. Park
Keyword(s):  
Plasminogen Activator ◽  
Formation Rate ◽  
Sodium Dodecyl ◽  
The Other ◽  
Tissue Type ◽  
Bromophenol Blue ◽  
Control Group ◽  
Fertilization In Vitro ◽  
Other Hand

Plasminogen activators (PAs) are serine proteases, known to be secreted by a large number of cell types, that convert plasminogen into plasmin. The present study was undertaken to identify PAs in porcine gametes and to investigate a possible role of plasminogen in fertilization in vitro in the pig. The oocyte maturation medium used was North Carolina State University-23 (NCSU-23) medium supplemented with 10% (v/v) porcine follicular fluid (pFF), 0.6 mM cysteine, 10 IU/mL human chorionic gonadotropin (hCG), and 10 IU/mL pregnant mare's serum gonadotropin (PMSG). To determine the changes of PA activities in porcine oocytes during maturation, the cumulus-oocyte complexes (COCs) were incubated in NCSU-33 in an atmosphere of 5% CO2 in air at 39�C for 0, 24, or 48 h. On the other hand, to investigate the release of PAs by boar spermatozoa, fresh spermatozoa were pre-incubated in fertilization medium (mTBM) for 0, 2, 4, or 6 h. After culture, 40 COCs, 40 cumulus-free oocytes, and 40 � 106 spermatozoa were separately put into microtubes containing 20 �L of sample buffer [5.0% (w:v) sodium dodecyl sulfate (SDS), 20% (v:v) glycerol, and 0.0025% (w:v) bromophenol blue in 0.125 M Tris-HCl buffer] and frozen at -80�C until used for analysis. PA activities in porcine oocytes and spermatozoa were quantified using SDS-PAGE, casein-agar zymography, and densitometry. Data were analyzed by ANOVA and Duncan's multiple-range test using the Statistical Analysis System (SAS Institute, Inc., Cary, NC, USA). In the COCs cultured for 24-18 h, tissue-type plasminogen activator (tPA), urokinase-type PA (uPA), and tPA-PA inhibitor (tPA-PAI) were observed. Also, PA activities increased as duration of culture increased. However, no uPA activity was detected in cumulus-free oocytes. In procine fresh spermatozoa, tPA, uPA, and tPA-PAI were observed. When spermatozoa were incubated for 2, 4, or 6 h in fertilization medium, the rate of acrosome reaction (AR) in spermatozoa increased as the duration of culture increased, but PA activities decreased gradually. However, PA activities in sperm-conditioned medium increased as duration of culture increased. On the other hand, to determine the effect of plasminogen on fertilization ability of porcine oocyte and spermatozoa, plasminogen (50 �g/mL) was added in fertilization medium. Addition of plasminogen to fertilization medium increased (P < 0.05) AR in spermatozoa and sperm binding to the zona pellucida (ZP), compared with control group. The ZP solubility (zona digestion time) was higher in medium with than that without plasminogen. When porcine oocytes and spermatozoa were co-incubated in fertilization medium with plasminogen, the polyspermic rate was lower in medium with than that without plasminogen. Also, plasminogen significantly (P < 0.05) increased formation rate of the male pronucleus in oocytes penetrated by spermatozoa. These results suggest that supplementing of plasminogen in fertilization medium may play a positive role in improving of fertilization ability in vitro in the pig.

338 EFFECTS OF CUMULUS CELLS AND FOLLICULAR FLUID ON PLASMINOGEN ACTIVATOR ACTIVITY AND OOCYTE MATURATION IN VITRO IN THE PIG

2006 ◽  
Vol 18 (2) ◽  
pp. 276
Author(s):  
C.-K. Park ◽  
J.-Y. An ◽  
S.-J. Sa ◽  
H.-T. Cheong ◽  
B.-K. Yang ◽  
...  
Keyword(s):  
Conditioned Medium ◽  
Oocyte Maturation ◽  
Follicular Fluid ◽  
Sodium Dodecyl ◽  
Cumulus Cells ◽  
The Other ◽  
Tissue Type ◽  
Bromophenol Blue ◽  
Maturation In Vitro

Plasminogen activators (PAs) are serine proteases, known to be secreted by a large number of cell type. PAs are reported to play a role in variety of physiologic processes, including fibrinolysis, ovulation, mammary involution, implantation, and fertilization. The present study investigated the effects of cumulus cells and porcine follicular fluid (pFF) on PA activity and oocyte maturation in vitro in the pig. Porcine oocytes were harvested from slaughterhouse ovaries, selected, and matured in modified North Carolina State University-23 (NCSU-23) media. After culture, cumulus-oocyte complexes (COCs) and denuded oocytes (DOs) were separately put into microtubes containing 20 �L of sample buffer [5.0% (w:v) sodium dodecyl sulfate, 20% (v:v) glycerol, and 0.0025% (w:v) bromophenol blue in 0.125 M Tris-HCl buffer] and frozen at -80�C until used for zymographic analysis. Differences in data were evaluated by Duncan's multiple-range test using the General Linear Models procedure in the Statistical Analysis System (SAS Institue, Inc., Cary, NC, USA). To determine the effect of porcine follicular fluid (pFF) on PA activity in porcine oocytes during maturation, the COCs and DOs were incubated in NCSU-23 medium with or without 10% (v/v) pFF for 0, 24, or 48 h. In the presence of cumulus cells, the proportions of oocytes matured to metaphase-II stage were significantly (P < 0.05) higher in medium with pFF than without pFF (69.8% vs. 37.7%, respectively). When COCs and DOs were cultured in the presence of pFF, tissue-type PA (tPA), urokinase-type PA (uPA), and tPA-PA inhibitor (tPA-PAI) were observed in COCs, and PA activities were higher at 48 h than 24 h. However, no PA activity was detected in DOs. Under the same conditions, when COCs and DOs were cultured in the absence of pFF, tPA and tPA-PAI were observed in COCs, and PA activities were increased as duration of culture increased. However, no PA activity was detected in DOs. When porcine oocytes were cultured in the presence of pFF, the activities of tPA-PAI, tPA, and uPA were observed in conditioned medium with COCs and DOs cultured for 24 h and 48 h. In the absence of pFF, PA activities were observed only in conditioned medium with COCs, and no PA activities were detected in conditioned medium with DOs. On the other hand, three plasminogen-dependent lytic bands (tPA-PAI, tPA, and uPA) were observed in pFF cultures. Particularly uPA activity was higher than the other kinds of PA activity. When oocytes and cumulus cells were separated from porcine COCs at 0 h of cultrue, tPA-PAI, tPA, and uPA were detected in cumulus cells at 48-h culture, but no PA activities were in DOs. The presence of pFF and cumulus cells in maturation medium stimulated not only nuclear and cytoplasmic maturation in porcine COCs, but also PA production by cumulus cells and COCs. It is possible that PAs produced by cumulus cells migrated through the gap junction between oocyte and cumulus cells. These results suggest that porcine oocytes have no ability to produce PA themselves.

scholarly journals Transcriptional, Mitochondrial Activity, and Viability of Egyptian Buffalo’s Granulosa Cells In Vitro Cultured under Heat Elevation

2021 ◽  
Vol 11 (2) ◽  
pp. 193-201
Author(s):  
Nasser Ghanem ◽  
Marwa Said Faheem ◽  
Romysa Samy ◽  
Ashraf Hesham Barkawi
Keyword(s):  
Heat Stress ◽  
Granulosa Cells ◽  
Transcriptional Activity ◽  
The Other ◽  
Control Group ◽  
Mitochondrial Activity ◽  
Fluorescent Intensity ◽  
Stressed Group ◽  
Other Hand

It is documented that heat stress caused impairment on the reproductive performance of dairy animals. However, there are few reports that have focused on the molecular and intracellular responses of in vitro cultured buffalo granulosa cells during heat elevation. The present study was conducted to investigate the effect of heat elevation during in vitro culture of buffalo granulosa cells on their viability, quality, mitochondrial activity, and transcriptional activity. Granulosa cells were harvested after aspiration of cumulus-oocytes complexes that were collected from abattoir ovaries. The granulosa cells were cultured in vitro either at a normal physiological temperature suitable for oocyte maturation and embryo development (38.5°C) or exposed to the elevated temperature of 40.5°C on day 3 of culture (the first two days were for confluence) for two hours of culture then continued at 38.5°C up to day 7 of culture. The viability of granulosa cells was measured using trypan blue and quality was estimated by measuring the level of intracellular reactive oxygen species (ROS) on day 7. Moreover, metabolic activity was performed by measuring the fluorescent intensity of mitochondria. Moreover, transcriptional activity was done by profiling four selected candidate genes using quantitative real-time PCR. The results indicated that the granulosa cells viability rate significantly decreased in the heat stress group (25.1 ± 3.7), compared to the control group (36.6 ± 5.3) on confluence day (day 3). In addition, the viability rate on the last day of culture (day 7) decreased in heat stress, compared to control (83.7 ± 4.5 and 97.4 ± 0.4, respectively). On the other hand, there was a nonsignificant difference in ROS profile between the control (21.7*104 ± 1.3) and the heat-stressed group (15.7 ± 0.7) on day 7 of culture. However, the mitochondrial fluorescent intensity was higher in the control (21.9 ± 1.9) than in the heat-stressed group (15.4 ± 0.8) on day 7 of culture. The expression of cellular defense (HSF1) and apoptosis-inducing gene (P53) were significantly up-regulated in granulosa cells exposed to heat elevation, compared to the control group. On the other hand, the steroidogenesis-regulating gene (StAR) was down-regulated in granulosa cells cultured under heat shock, compared to the control group. In conclusion, heat stress reduced the viability of granulosa cells by inducing the expression of an apoptosis-related gene (P53) and compromised expression of genes regulating the steroid biosynthesis, which resulted in up-regulation of cell defense gene (HSF1) in an attempt to ameliorate the deleterious effect of heat stress on the biological activity of the granulosa cells.

404 DNA TAKE-UP BY SPERM AND IN VITRO EMBRYO DEVELOPMENT BY SPERM-MEDIATED GENE TRANSFER IN THE PIG

2007 ◽  
Vol 19 (1) ◽  
pp. 317
Author(s):  
T. S. Kim ◽  
Y. Cao ◽  
H. T. Cheong ◽  
B. K. Yang ◽  
C. K. Park
Keyword(s):  
Gene Transfer ◽  
Transfection Efficiency ◽  
The Other ◽  
Control Group ◽  
Dna Uptake ◽  
Alkaline Lysis ◽  
Exogenous Dna ◽  
Other Hand ◽  
Dna Complex

Sperm mediated gene transfer (SMGT) is based on the ability of spermatozoa to bind and internalize exogenous DNA and transfer it into the oocytes at fertilization. The purpose of this study was to assess introducing exogenous DNA into boar spermatozoa by DNA solution or DNA/liposome complex under different conditions (period of incubation, exogenous DNA, liposome, and concentration of spermatozoa). Genomic DNA of sperm loaded with DNA by treatment was isolated by alkaline lysis. Quantitation of exogenous DNA amplified by PCR was analyzed by agarose electrophoresis densitometry. The quality of treated spermatozoa under the best conditions or no treatment (control) was evaluated during incubation (0, 2, 4, and 6 h) for viability (SYBR-14/PI), motility (Makler counting chamber), morphology (rose bengal staining), and acrosomal status (Coomassie staining). Sperm loaded with DNA also were used for in vitro fertilization. Immature oocytes incubated in TCM-199 medium for 44 h were fertilized in mTBM medium for 6 h and cultured in PZM-3. Cleavage and development of embryos were assessed on Days 2 and 7 of culture, respectively. Transfection rates at the blastocyst stage were assessed by PCR analysis. Data were evaluated by Duncan&apos;s multiple-range test using the GLM procedure. In the preliminary experiment, DNA uptake of spermatozoa by DNA solution and liposome/DNA complex was completed within 90-120 min. Transfection efficiency of spermatozoa was significantly (P &lt; 0.05) higher in the 105 spermatozoa group than in the other groups (104, 106, and 107 spermatozoa). The transfection efficiency was gradually increased by increasing the concentration of exogenous DNA. On the other hand, viability of transfected spermatozoa by all treatments (control, DNA solution, and DNA/liposome) at 0 h (72.3 � 0.2, 70.8 � 1.8, and 68.0 � 2.2%, respectively) of storage was significantly (P &lt; 0.05) lower than for fresh spermatozoa (83.3 � 1.7%). Survival and motility of all treatments after 4 h of storage were significantly (P &lt; 0.05) lower than at 0 and 2 h. Both abnormality and acrosome reaction of spermatozoa were gradually increased with prolonged storage periods. On the other hand, the cleavage rate of embryos by DNA/liposome complex (56.3 � 2.3%) was significantly (P &lt; 0.05) lower compared to both DNA solution (64.0 � 1.1%) and control (67.8 � 2.3%). The developmental rates of blastocysts were significantly (P &lt; 0.05) lower in the liposome/DNA complex and DNA solution groups (9.1 � 1.3 and 11.3 � 0.8%) than in the control group (22.2 � 0.6%). The transfection rates of blastocysts were higher in the liposome/DNA group (54.3 � 12.0%) than in the DNA solution group (38.7 � 6.6%). These results show that the SMGT method under the control conditions efficiently transfers exogenous DNA into the porcine oocytes. This work was supported by the Research on the Production of Bio-organs (No. 2005 03020302) Ministry of Agriculture and Forestry, Republic of Korea

Studies on the Specific Fibrinolytic Effect of Human Extrinsic (Tissue-Type) Plasminogen Activator in Human Blood and in Various Animal Species in Vitro

1981 ◽  
Vol 46 (02) ◽  
pp. 561-565 ◽  
Author(s):  
C Korninger ◽  
D Collen
Keyword(s):  
Human Plasma ◽  
Plasminogen Activator ◽  
Culture Fluid ◽  
The Other ◽  
Tissue Type ◽  
Chain Molecule ◽  
Autologous Plasma ◽  
Tissue Type Plasminogen Activator ◽  
Type Plasminogen Activator

SummaryHuman extrinsic (tissue-type) plasminogen activator (EPA) was highly purified from the culture fluid of a human melanoma cell line, both as a one-chain or as a two-chain molecule. Its specific fibrinolytic effect on human whole blood clots or plasma clots with different degrees of fibrin crosslinking was evaluated in an in vitro system, composed of a 125I-fibrin labeled clot, hanging in circulating human plasma. After infusion of EPA (30 IU per ml over 3 hrs), non-crosslinked clots lysed more extensively (75-100 percent in 5 hrs) than totally-crosslinked clots (50-65 percent), and no difference was found between one-chain or two-chain EPA. The extent of lysis of totally-crosslinked human or animal plasma clots hanging in autologous plasma induced by EPA varied markedly from one species to the other. When 90 IU of EPA were infused over 3 hrs, crosslinked human plasma clots dissolved for over 95 percent within 5 hrs. Under comparable conditions, the degree of lysis was 80 percent in primate plasma (cynomolgus fascicularis), 60 percent in cat and rabbit plasma, 30 percent in dog plasma and only 10 percent in rat plasma. Systemic activation of the fibrinolytic system in the circulating plasmas was minor and dose-dependent in all species, but complete fibrinogen breakdown was not observed in any species following infusion of up to 90 IU EPA per ml plasma.It is concluded that the human system is more susceptible to EPA induced fibrinolysis than the other animal systems which were investigated, and that even totally-crosslinked clots can be lysed after infusion of EPA.

BOVINE PULMONARY ARTERY ENDOTHELIAL CELLS (BPAECs) STIMULATE TISSUE TYPE PLASMINOGEN ACTIVATOR (tPA) RELEASE BY HUMAN MELANOMA CELL LINES (HMCLs)

1987 ◽  
Author(s):  
J Wojta ◽  
M Vetterlein ◽  
R N Eoover
Keyword(s):  
Endothelial Cells ◽  
Plasminogen Activator ◽  
Active Form ◽  
Plasminogen Activator Inhibitor ◽  
Activity Level ◽  
The Other ◽  
Tissue Type ◽  
Malignant Cells ◽  
Other Hand ◽  
Type Plasminogen Activator

It is known that treatment of endothelial cells (ECs) with extracts of malignant cells results in an increased level of tPA release by such ECs. On the other hand, no data are available concerning an influence of ECs on the fibrinolytic activity (PA) of malignant cells. Therefore it was the aim of this investigation to study whether the tPA production of malignant cells is influenced by ECs. Eighteen different HMCLs were screened for their ability to produce tPA using a combined assay system for tPA activity and tPA antigen employing monoclonal anti tPA antibodies. All 18 HMCLs produced tPA antigen ranging from 0.2 to 15.5ng/105 cells/24 hours. Twelve of these cells produced also tPA activity from 0.2 to 5.0 IU/105 cells/24 hours. To determine the influence of ECs on the PA of HMCLs, BPAECs were selected because their PA consists mainly of urokinase type plasminogen activator (uPA). All 18 HMCLs were cultivated on monolayers of BPAECs and as a control on plastic. After 24 hours the average tPA antigen level in the supernatant for the HMCLs grown on monolayers of BPAECs was 4.2ng/105 cells as compared to 2.9ng/105 cells of the control. However, the tPA activity average level was < 0.1 IU/105 cells for the HMCLs grown on BPAECs and 0.9 IU/105 cells for the HMCLs grown on plastic. To further investigate these effects two HMCLs were grown on plastic and incubated with conditioned media (CM) of BPAECs and compared to non conditioned medium (NCM). After 24 hours the levels of tPA antigen in the supernatant were 194 and 28.5ng/l05 cells after incubation with CM and compared to 14.0 and 14.9ng/105 cells for the control. In contrast to the first experiment the tPA activity level was also increased after incubation with CM. The respective values were 9.5 and 11.6 IU/105 cells and 3.8 and 4.8 IU/105 cells for the control. Our data suggest that BPAECs release a "factor" which is stimulating both the release of tPA activity and tPA antigen. This "factor" remains to be further characterized. On the other hand our results also suggest that BPAECs might release a plasminogen activator inhibitor (PAI) in its active form inhibiting the tPA simultanously released by cocultivated HMCLs.

scholarly journals Thrombolytic properties of staphylokinase

Blood ◽  
1990 ◽  
Vol 76 (5) ◽  
pp. 925-929
Author(s):  
O Matsuo ◽  
K Okada ◽  
H Fukao ◽  
Y Tomioka ◽  
S Ueshima ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Human Plasma ◽  
Plasminogen Activator ◽  
The Other ◽  
Tissue Type ◽  
Plasminogen Activation ◽  
Plasma Clot ◽  
Tissue Type Plasminogen Activator ◽  
Other Hand ◽  
Type Plasminogen Activator

We evaluated the properties of recombinant staphylokinase in comparison with those of tissue-type plasminogen activator (t-PA) and streptokinase (SK). The presence of fibrin(ogen) fragment FCB-2 in the reaction mixture increased plasminogen activation by staphylokinase more than 20-fold. Such characteristics are similar to those of t-PA. On the other hand, SK was not affected by the presence of FCB-2. The thrombolytic properties of staphylokinase were studied in a system consisting of a radioactive human plasma clot (125I-fibrinogen-labeled) suspended in the circulating citrated plasma. Significant thrombolysis (50% in 3 hours) was obtained with 2 micrograms/mL of staphylokinase and 4.45 micrograms/mL t-PA, as compared with 12 micrograms/mL for SK. The relative molar potency of staphylokinase, calculated from the molecular weight, was about two times more effective than that of SK, but about half of that of t-PA. Systemic fibrinolytic activation and fibrinogen breakdown was not observed with staphylokinase or t-PA, but was observed with SK. The thrombolytic efficiency of staphylokinase, which was calculated as the ratio of the degree of thrombolysis/the degree of fibrinogenolysis, was about five times greater than that of SK, and about half of that of t-PA. These findings suggest that staphylokinase has higher specific thrombolytic properties and lesser fibrinogenolytic properties than those of SK.

Evaluating Hemolytic and Photo Hemolytic Potential of Organophosphorus by In Vitro Method as an Alternative Tool Using Human Erythrocytes

2020 ◽  
Vol 20 (9) ◽  
pp. 738-745 ◽  
Author(s):  
Ana L.G. Soria ◽  
Fabiola R. Ramirez ◽  
Alberto B. Pliego ◽  
Héctor R.D. Guadarrama ◽  
Guadalupe P.M. Farrera ◽  
...  
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
Methyl Parathion ◽  
Sodium Dodecyl ◽  
Human Erythrocytes ◽  
The Other ◽  
In Vitro Assays ◽  
Haemolytic Activity ◽  
Other Hand

Aims: The present study aims to determine the phototoxic and haemolytic activity of organophosphorus. The use of alternative in vitro assays with human erythrocytes is suggested to predict the polluting effect of these products on health. Methodology: Human erythrocytes from Toluca Blood Bank were used. Sodium dodecyl sulfate was employed as a positive control. Additionally, the haemolysis percentage of three organophosphate (Acetate, Chlorpyrifos, Malathion, Methamidophos, Methyl Parathion) induced photo haemolysis formulated with surfactants on a concentration of 2 x 109 erythrocytes were evaluated. Finally, the products were classified as irritant or phototoxic. Results: Results showed that the HC50 red blood cells were similar for each organophosphate (Malathion and Methamidophos) indicating very irritant action with ratio classification (L/D) of 0.041 and 0.053, respectively. On the other hand, Chlorpyrifos was classified as an irritant with L/D= 0.14. On the other hand, the HC50 obtained photo hemolysis assays irradiated red blood cells was similar for each organophosphate (Acetate, Chlorpyrifos, Malathion, Methamidophos, Methyl Parathion) indicating no phototoxic action. Conclusion: As a conclusion, it can be said that the parameters of haemolysis and denaturation of proteins are good indicators to classify organophosphorus formulated with surfactants as irritating or phototoxic.

scholarly journals Thrombolytic properties of staphylokinase

Blood ◽  
1990 ◽  
Vol 76 (5) ◽  
pp. 925-929 ◽  
Author(s):  
O Matsuo ◽  
K Okada ◽  
H Fukao ◽  
Y Tomioka ◽  
S Ueshima ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Human Plasma ◽  
Plasminogen Activator ◽  
The Other ◽  
Tissue Type ◽  
Plasminogen Activation ◽  
Plasma Clot ◽  
Tissue Type Plasminogen Activator ◽  
Other Hand ◽  
Type Plasminogen Activator

Abstract We evaluated the properties of recombinant staphylokinase in comparison with those of tissue-type plasminogen activator (t-PA) and streptokinase (SK). The presence of fibrin(ogen) fragment FCB-2 in the reaction mixture increased plasminogen activation by staphylokinase more than 20-fold. Such characteristics are similar to those of t-PA. On the other hand, SK was not affected by the presence of FCB-2. The thrombolytic properties of staphylokinase were studied in a system consisting of a radioactive human plasma clot (125I-fibrinogen-labeled) suspended in the circulating citrated plasma. Significant thrombolysis (50% in 3 hours) was obtained with 2 micrograms/mL of staphylokinase and 4.45 micrograms/mL t-PA, as compared with 12 micrograms/mL for SK. The relative molar potency of staphylokinase, calculated from the molecular weight, was about two times more effective than that of SK, but about half of that of t-PA. Systemic fibrinolytic activation and fibrinogen breakdown was not observed with staphylokinase or t-PA, but was observed with SK. The thrombolytic efficiency of staphylokinase, which was calculated as the ratio of the degree of thrombolysis/the degree of fibrinogenolysis, was about five times greater than that of SK, and about half of that of t-PA. These findings suggest that staphylokinase has higher specific thrombolytic properties and lesser fibrinogenolytic properties than those of SK.

Fibrin-specificity of a Plasminogen Activator Affects the Efficiency of Fibrinolysis and Responsiveness to Ultrasound: Comparison of Nine Plasminogen Activators In Vitro

1999 ◽  
Vol 81 (04) ◽  
pp. 605-612 ◽  
Author(s):  
Dmitry V. Sakharov ◽  
Marrie Barrett-Bergshoeff ◽  
Rob T. Hekkenberg ◽  
Dingeman C. Rijken
Keyword(s):  
Thrombolytic Therapy ◽  
Plasminogen Activator ◽  
Tissue Type ◽  
Bolus Administration ◽  
High Frequency Ultrasound ◽  
Single Chain ◽  
Response Curves ◽  
Maximal Speed ◽  
Frequency Ultrasound

SummaryIn a number of cases, thrombolytic therapy fails to re-open occluded blood vessels, possibly due to the occurrence of thrombi resistant to lysis. We investigated in vitro how the lysis of hardly lysable model thrombi depends on the choice of the plasminogen activator (PA) and is accelerated by ultrasonic irradiation. Lysis of compacted crosslinked human plasma clots was measured after addition of nine different PAs to the surrounding plasma and the effect of 3 MHz ultrasound on the speed of lysis was assessed.Fibrin-specific PAs showed bell-shaped dose-response curves of varying width and height. PAs with improved fibrin-specificity (staphylokinase, the TNK variant of tissue-type PA [tPA], and the PA from the saliva of the Desmodus rotundus bat) induced rapid lysis in concentration ranges (80-, 260-, and 3,500-fold ranges, respectively) much wider than that for tPA (a 35-fold range). However, in terms of speed of lysis, these three PAs exceeded tPA only slightly. Reteplase and single-chain urokinase were comparable to tPA, whereas two-chain urokinase, anistreplase, and streptokinase were inferior to tPA. In the case of fibrin-specific PAs, ultrasonic treatment accelerated lysis about 1.5-fold. For streptokinase no acceleration was observed. The effect of ultrasound correlated with the presence of plasminogen in the outer plasma, suggesting that it was mediated by facilitating the transport of plasminogen to the surface of the clot.In conclusion, PAs with improved fibrin-specificity induce rapid lysis of plasminogen-poor compacted plasma clots in much wider concentration ranges than tPA. This offers a possibility of using single-or double-bolus administration regimens for such PAs. However, it is not likely that administration of these PAs will directly cause a dramatic increase in the rate of re-opening of the occluded arteries since they are only moderately superior to tPA in terms of maximal speed of lysis. Application of high-frequency ultrasound as an adjunct to thrombolytic therapy may increase the treatment efficiency, particularly in conjunction with fibrin-specific PAs.

Deep Vein Thrombosis and Fibrinolysis

1991 ◽  
Vol 66 (04) ◽  
pp. 426-429 ◽  
Author(s):  
Marcel Levi ◽  
Anthonie W A Lensing ◽  
Harry R Büller ◽  
Paolo Prandoni ◽  
Gerard Dooijewaard ◽  
...  
Keyword(s):  
Deep Vein Thrombosis ◽  
Plasminogen Activator ◽  
Plasminogen Activator Inhibitor ◽  
Tissue Type ◽  
Controlled Study ◽  
First Episode ◽  
Control Group ◽  
Vein Thrombosis ◽  
Type Plasminogen Activator ◽  
Deep Vein

SummaryIn the present study 57 consecutive patients with a first episode of venographically proven deep vein thrombosis were investigated to evaluate the release of tissue-type plasminogen activator (t-PA) and of urokinase-type plasminogen activator (u-PA) in response to DDAVP stimulation as well as the resting plasminogen activator inhibitor (PAI) concentration, comparing this to the results obtained in 66 similar patients with a clinical suspicion of thrombosis but with a normal venogram. All assays were performed without knowledge of the patient's status.Four patients in the deep vein thrombosis-group (7%) had an absent u-PA antigen response upon DDAVP infusion, while a normal response was observed in all control subjects. Patients and controls showed similar increases in t-PA antigen level upon DDAVP. High resting PAI antigen levels were encountered in 5 patients in the deep vein thrombosis-group (9%) and in 6 subjects in the control group (9%).The results from this controlled study indicate that a defective release of u-PA may occur in patients with deep vein thrombosis and may have pathogenetic significance. Furthermore it is concluded that elevation of PAI levels cannot be considered as a specific risk factor for venous thrombosis.

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