Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.21.7 (plasmin)
 9,023 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Pig plasmin (Lysofibrin) was given to 11 patients with phlebographically verified venous thrombosis, 2 of whom were treated two and three times, respectively. The effect on coagulation and fibrinolytic parameters was studied. The platelet count, Owren's P&P (prothrombin plus factors VII and X), plasminogen, factor XIII, and antithrombin III did not change during the treatment. All patients developed a proteolytic activity demonstrable on both unheated and heated fibrin plates. The fibrinogen decreased successively to very low levels, and parallel to this an increase in fibrin/fibrinogen degradation products was found. The factor VIII and factor V activities decreased immediately after each Lysofibrin infusion but normalized rapidly again. The factor VIII molecule, however, retained its reactivity to rabbit antiserum against factor VIII. Immediately after the plasmin infusion a decrease of both alpha2-macroglobulin (alpha2-M) and the rapidly reacting alpha2-antiplasmin was observed. alpha2-M decreased successively and in several of the patients values were unmeasurable for a period of some days. A complex formation between pig plasmin and the alpha2-antiplasmin was demonstrated in crossed immunoelectrophoresis. The complexes were rapidly cleared from the circulation. No interaction between the pig plasmin and the inhibitor of the plasminogen activation, alpha1-antitrypsin or inter-alpha-inhibitor, was found.
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PMID:Effects of porcine plasmin on the coagulation and fibrinolytic systems in humans. 7 91

The simultaneous additon of suboptimal concentrations of factor VIII and intact or plasmin-lysed fibrinogen into mixtures of the vitamin K dependent factors, phospholipids, adsorbed bovine serum (supplier to factor V) and calcium, increased the amount of thrombin which was generated three to twenty times over the sum of the amounts which were generated when factor VIII, or fibrinogen, or its derivatives were added separately into the thrombin generating mixture. When factor VIII was added together with both fibrinogen and its derivatives, the amount of thrombin generated was even greater, about 130% larger than the amount which was generated in the presence of equal concentrations of only intact fibrinogen plus factor VIII. Addition of albumin instead of fibrinogen or its derivatives has a similar but significantly lower effect on thrombin generation. It appears, therefore, that both intact fibrinogen and its plasminolytic derivatives, singly or in combination, and to a lesser extent albumin, act as cofactors in the reaction which is regulated by factor VIII.
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PMID:Fibrinogen and its derivatives: cofactors in the intrinsic generation of thrombin. 98 30

We describe six new cases of a hemorrhagic diathesis induced by contact with Lonomia achelous caterpillars. Onset of clinical bleeding varied between a few hours and 10 days post-exposure. Laboratory coagulation tests showed prolonged PT, PTT and ThT; normal platelets and a marked decrease of fibrinogen, factor V, plasminogen and factor XIII (including its subunits A and S). Factors VII, II and alfa 2 anti-plasmin were variably affected. In addition, activation of the fibrinolytic system and the generation of a procoagulant effect could also be demonstrated. Two cases developed severe hemorrhagic diathesis and one of them died of a cerebral hemorrhage. Different aspects of this rare syndrome are discussed in relation to its complex physiopathology and the variability observed in all clinical and laboratory manifestations. Therapeutic recommendations and some possible hazards following replacement transfusions are also considered.
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PMID:Six new cases of a caterpillar-induced bleeding syndrome. 137 51

This study examines the assumption that both the anticoagulant and fibrinolytic activity that follow the generation of thrombin induced by infusion of factor Xa/PCPS are due to generation of activated protein C. Untreated controls or animals given unrelated antibody were compared with animals pretreated with a specific monoclonal antibody to protein C (HPC4). Compared with untreated controls excess HPC4 substantially reduced the level of protein C activation as observed by protein C immunoblotting and enzyme-linked immunosorbent assay for antitrypsin/activated protein C complexes. Despite this, the anticoagulant activity as reflected by the decline of factors Va and VIIIa levels (as observed by coagulation assays and by factor V immunoblotting) was significantly greater than controls. The fibrinolytic activity (as observed by assays of tissue plasminogen activator, D-Dimer, alpha 2-antiplasmin) also was significantly greater than controls. We conclude that neutralization of the protein C anticoagulant system while resulting in a significantly more intense coagulant response to Xa/PCPS does not preclude inactivation of factors Va and VIIIa and the full expression of the fibrinolytic response. We conclude further that after thrombin generation in vivo, protein C activation is not a prerequisite for the promotion of the fibrinolytic response previously observed, and that the inactivation of factors Va/VIIIa may be mediated by enzymes other than activated protein C. The reduction in alpha 2-antiplasmin levels in association with increased tissue plasminogen activator activity suggests that plasmin is a likely candidate.
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PMID:Anticoagulant and fibrinolytic activities are promoted, not retarded, in vivo after thrombin generation in the presence of a monoclonal antibody that inhibits activation of protein C. 155 68

Thirty-six patients with chronic myeloproliferative disorders (CMPD) were studied as regards blood coagulation and fibrinolysis. These studies revealed various mild abnormalities: activated thromboplastin time (APTT) tended to prolong and the level of factor V decreased significantly. In several cases, the levels of D-dimer, thrombin-antithrombin III complex and plasmin-alpha 2-plasmin inhibitor complex were elevated compared to normal. These results suggest that abnormal coagulation system in the patients with CMPD is related to low grade disseminated intravascular coagulation. Many coagulation factors did not correlate with peripheral blood cell counts. Two patients with polycythemia vera were evaluated for several abnormalities of the coagulation system before and during treatment. Coagulation abnormalities persisted after hematologic control had been achieved. Our results suggest that patients with CMPD have a chronic state of abnormal blood coagulation system even after normalization of blood cell counts.
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PMID:[Abnormal blood coagulation and fibrinolysis in chronic myeloproliferative disorders]. 187 Feb 70

Unstable angina is a clinical syndrome of recurrent myocardial ischemia. In some cases, this reflects episodic platelet activation and coronary thrombosis. Thus, the biosynthesis of thromboxane A2, which is largely derived from activated platelets, is increased, often coincident with chest pain. The major role of platelets in unstable angina may influence the response to plasminogen activators. Platelets increase the resistance of thrombi to lysis, by inducing clot retraction and cross-linking and by releasing inhibitors. Thus, coronary thrombi in unstable angina may be resistant to lysis. Furthermore, both t-PA and streptokinase cause platelet activation and thrombin formation in vivo, possibly via plasmin. Plasmin can activate platelets and factor V directly. These prothrombotic effects of plasminogen activators may limit their activity in unstable angina. At the very least, their therapeutic efficacy may be highly dependent on the coadministration of potent antiplatelet agents and anticoagulants.
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PMID:Platelet activation in the pathogenesis of unstable angina: importance in determining the response to plasminogen activators. 189 67

The effects of medroxyprogesterone acetate (MPA) on the mechanism of coagulation in postmenopausal patients were studied and compared with those of tamoxifen by a retrospective analysis. The coagulation test parameters tested included platelet count, bleeding time, clotting time, prothrombin time, activated partial thromboplastin time, and the levels of fibrinogen, fibrin degradation products, factor II, factor V, plasminogen, alpha 2-plasmin inhibitor (alpha 2-PI) and alpha 2-plasmin inhibitor-plasmin complex (alpha 2-PI-P). A shortened APTT was noted and the levels of factors II, V, alpha 2-PI and alpha 2-PI-P were also out of the normal range during treatment in the MPA-treated group. However, these abnormal parameters recovered to within the normal range from 6 months or more after the commencement of treatment without any termination of drug administration. The patients were all asymptomatic. In contrast, a slight prolongation of bleeding time which persisted for more than 6 months was observed in the patients treated with tamoxifen. These data suggest that MPA causes a hypercoagulable state and that any change must be carefully monitored during treatment with either MPA or tamoxifen.
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PMID:The induction of a hypercoagulable state by medroxyprogesterone acetate in breast cancer patients. 215 Jun 78

Studies of the clotting mechanisms in the plasma of a Burmese python (Python molurus bivittatus) confirm earlier information that both extrinsic and intrinsic pathways of thrombin formation participate in reptilian hemostasis. Plasma fibrinogen was present at a concentration comparable to that in human plasma. Other assays were hampered by the need to use nonreptilian reagents. The activated partial thromboplastin time was shorter than was that of human plasma, thus implying the presence of prothrombin in python plasma; however, this protein could be demonstrated only in trace amounts. Similarly, only small amounts of Hageman factor (factor XII) and antihemophilic factor (factor VIII) were detected, and none of plasma prekallikrein, high-molecular-weight kininogen, and Christmas factor (factor IX). The prothrombin time was slower than that of human plasma. Factor VII was not detected, but both proaccelerin (factor V) and Stuart factor (factor X) were present. Python plasma inhibited bovine thrombin and human plasmin, but it was deficient in fibrinolytic capacity.
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PMID:Notes on clotting in a Burmese python (Python molurus bivittatus). 234 66

Thrombin (Thr), plasmin (Pl) and elastase (ELP) are serine proteinases which are quickly inactivated by their specific inhibitors (AT III, alpha 2AP, alpha 1AT), if intravascular activation of coagulation and fibrinolytic system or if release from PMN granulocytes by different stimuli (F.I., endotoxin, activated factor XII, a.o.) occurs. The immunological determination of the developing proteinase inhibitor complexes (PIC) AT III-Thr, alpha 2AP-Pl and alpha 1AT-ELP gives information as to whether intravascular coagulation, hyperfibrinolysis or unspecific proteolysis induced by elastase have taken place. Despite the high antiprotease activity in the plasma the a.m. serine proteinases may exert their proteolytic activity towards their specific substrates in vivo. In infectious diseases, fulminant hepatic failure and cardiac shock a complex consumption of coagulation factors and inhibitors may cause severe coagulation defects, microcirculatory disturbances and bleeding tendency. The PICs behaviour was determined in more than 80 patients with infectious diseases, in 5 patients with fulminant hepatic failure (FHF) and 7 patients with cardiac shock. Only in infectious diseases, mainly in septic complications, and septic complications during FHF and cardiac shock, are alpha 1AT-ELP levels found to be highly elevated. After cardiac shock, in FHF and in infectious diseases coagulation and fibrinolysis may additionally be activated. In this case AT III-Thr and alpha 2AP-Pl complexes could be detected in the patients plasma. This indicates that intravascular coagulation and hyperfibrinolysis has additionally taken place. To prevent bleeding complications a replacement therapy with plasma derivatives (AT III, plasminogen concentrate, PPSB and FFP) has been successfully performed in several patients with septic complications and in the 5 patients with FHF and the 7 patients with cardiac shock. No bleeding complication occurred, and the haemostatic balance could be maintained in the treated patients. AT III replacement therapy is necessary to stop DIC, PPSB improves severe coagulation defects, only FFP may additionally provide alpha 1AT, alpha 2AP and factor V. In acute renal failure sometimes plasminogen replacement is necessary to maintain a normal activity of the fibrinolytic system. The complex consumption of coagulation proteins in infectious diseases, FHF and cardiac shock cannot successfully be treated with an anticoagulant such as heparin alone.
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PMID:The proteinase inhibitor complexes (antithrombin III-thrombin, alpha 2antiplasmin-plasmin and alpha 1antitrypsin-elastase) in septicemia, fulminant hepatic failure and cardiac shock: value for diagnosis and therapy control in DIC/F syndrome. 242 25

The effect of human plasmin on human coagulation factor V was studied using isolated proteins. Incubation of factor V with plasmin resulted in a rapid increase in procoagulant activity, followed by a subsequent decline in the ability of factor V to serve as a cofactor in the prothrombinase complex. Identical results were obtained when these reactions were conducted in the presence of dansylarginine-N-(3-ethyl-1,5-pentanediyl) amide (DAPA), indicating that the changes observed could not have occurred as a consequence of cleavage by alpha-thrombin. Analysis of the products of the reaction by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) revealed a temporal correlation between the rise and fall in factor V activity and the presence of several transient intermediates. These fragments are distinct from the subunits of alpha-thrombin-activated factor V (factor Va). The activation phase of the reaction was not significantly affected by the presence of phospholipid. In contrast, the rate of degradation of active fragments of factor V and the accompanying loss of activity were markedly enhanced in the presence of phospholipid vesicles. These data suggest that the action of plasmin upon factor V results in the transient formation of proteolytic fragments which express significant procoagulant activity.
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PMID:Activation/inactivation of human factor V by plasmin. 252 Dec 93


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