Changes In Fibrinolytic Activity Research Articles

Changes of Fibrinolytic Activity in Blood with Normal Humans in Case of the Administration of Dextran Sulphate (3g)

We have reported that the concomitant administration of urokinase (UK) and dextran sulphate (DS) has induced higher fibrinolytic activity than that expected from the simple addition of UK alone or DS alone. For clarifying the mechanism of the accelerated (or sustained) fibrinolytic activity induced by concomitant administration of UK and DS, a large amount (3g) of DS alone was administered to the three healthy adults, and the change of the fibrinolytic activity was then estimated using fibrin plates and the content of the various factors of coagulation, fibrinolysis and kinin system in the blood were estimated by the method of single radial immunodiffusion. After DS administration, three volunteers did not have any side effects and plasmin activity in the blood increased two folds before DS administration.Furthermore, % reduction of fibrinogen content in plasma after DS administration was 19.9, that of α2-macroglobulin content was 10, that of α1-antitrypsin content was 10, that of C1'-inactivator content was 7.4, that of prothrombin content was 7.2, that of antithrombin III content was 5.6 and that of plasminogen content was 2.0.On the other hand, the fibrinolytic activity in the euglobulin fraction increased markedly after DS administration, the fibrinolytic activity curvemoved upwords and counter-clockwise.Based on the above-mentioned results, it was appeared that the acceleration of the fibrinolytic activity after the concomitant administration of UK and DS was due to decreasing the inhibitory activity of inhibitors after DS administraion alone.

Arthus Tonsillitis in the Rabbit: Histological Findings and Fibrinolytic Activity in the Blood

Arthus-type hypersensitivity was induced experimentally in the tonsils of rabbits. Histopathological studies were performed on the Arthus tonsillitis so produced, and estimations of the plasma fibrinolytic activity were made on the blood of these rabbits. The findings obtained by macroscopic inspection of the tonsil revealed significant bleeding and swelling. Furthermore, the histopathological studies demonstrated bleed and infiltration of leukocytes into various parts of the parenchyma and connective tissue surrounding the tonsil during the early stages of tonsillitis. From the results concerning certain parameters of the fibrinolytic system in the blood, it was demonstrated that, during the early stage of tonsillitis, the fibrinolytic activity increased and whole plasmin was consumed. Based on the above findings, it seems that the change in fibrinolytic activity found in rabbits affected by Arthus tonsillitis closely resembles that in patients suffering from acute tonsillitis.

An Experimental Study of Systemic and Local Fibrinolysis in Respiratory Tract Inflammation in Specific Pathogen Free Rabbits

An experimental animal model with inflammation of the respiratory tract was prepared using specific-pathogen-free (SPF) rabbits and exposing them to both O3 and bacteria (Bordetella bronchiseptica).In this experiment, the relation between the progress of inflammation and the changes in fibrinolytic activities in the local tissues and in the blood was studied.The results obstained were as follows:1. Microscopic observations of the respiratory tract showed that the strongest inflammatory change occurred 7 days after the exposure of the animals to the O3 and bacteria for 3 days. Recovery was observed after 28 days.2. The plasma fibrinogen level clearly increased along with the histological changes in the trachea and nasal septum, reached the maximum level on the 7th day and decreased to the normal level thereafter. The local fibrinolytic activity also changed along with the fibrinogen level.3. The fibrinolytic activity in the euglobulin fractions was observed to reach its maximum on the 14th day.4. The injection of t-AMCHA showed an inhibitory effect against both local and blood fibrinolysis, while the occurrence of respiratory inflammation and an increase in fibrinogen were not affected for the first 7 days. The administration of t-AMCHA was considered to promote healing of the experimental inflammation. The fibrinolysis in this model is considered to be one of the exacerbating factors for respiratory inflammation.

Plasma fibrinolysis and postoperative deep vein thrombosis.

In 23 high risk patients the change in plasminogen activator activity in response to surgical operation was studied by euglobulin lysis time (ELT) and fibrin plate lysis before, during and for up to 6 days following a major surgical procedure. Fibrin degradation products (FDP) were also measured. The aim was to relate any changes to postoperative deep vein thrombosis (DVT) as diagnosed by the 125I fibrinogen test. Peroperative increase and postoperative inhibition of fibrinolytic activity were seen in all the patients. Changes in fibrinolytic activity as measured by the ELT and during the first 24 hours by the fibrin plate technique were similar. This suggests that during this period the response was independent of plasma fibrinogen changes. There was no significant difference in these parameters between patients who developed DVT and those who did not. The relationship between venous thrombo-embolism and elevation of serum FDP was confirmed.

Fibrinolytic and hemostatic changes during and after maximal exercise in males.

To evaluate changes in fibrinolytic activity, factor VIII and other hematological variables during and after a progressive step increment in work load, 10 healthy male subjects (22-27 yr of age) were exercised to exhaustion on an electromagnetic bicycle ergometer. Blood samples were drawn serially throughout the experiment. Little change in fibrinolytic activity was observed before 70-80% maximum heart rate (MHR) was achieved. Major changes occurred after 80% MHR. Peak values coincided with maximum exercise. In contrast major changes in factor VIII were observed between 95 and 100% MHR with peak values occurring 5-10 min postexercise. An increase in white blood cell count, platelet count, and retention was observed at maximum exercise. One individual failed to demonstrate an increase in either fibrinolytic or factor VIII activity. Relating the data to either the percent maximal oxygen uptake or percent maximal heart rate demonstrates the importance of the exercise protocol and exerting all subjects to the same relative level of physiological work.

Decreased Fibrinolysis in Reperfused Ischaemic Tissue

SummaryThe fibrinolytic activity of skin flaps subjected to ischaemia and reperfusion was studied in five pigs. Total interference with the blood supply up to 24 hours did not in itself lead to changes in fibrinolytic activity. However, reperfusion of the skin after six hours of ischaemia caused a dramatic reduction in fibrinolytic activity measured 18 hours later.Similar studies on reperfused femoral artery and vein after six hours of ischaemia showed marked reduction in fibrinolytic activity of the vessels.It is suggested that reperfusion of tissue made ischaemic for six hours is damaging and might be a contributory factor to vascular pathology.

Reversal of abnormal fibrinolytic activity, blood coagulation factors and platelet function in high-altitude pulmonary oedema with frusemide.

In high-altitude pulmonary oedema there is evidence of widespread intravascular clotting which is associated with and may result from reduced fibrinolytic activity with increased plasma fibrinogen, increased factors V, VIII and X, decreased factor XII, and increased platelet adhesiveness and platelet factor 3. The beneficial effect of frusemide which is the mainstay of treatment has so far been ascribed to its potency and rapidity of action in inducing diuresis and its effect on pulmonary blood volume which is reduced. However, an interesting new finding is that at the same time frusemide reverses adverse changes in fibrinolytic activity, blood coagulation, and platelet function and thereby removes impediment to the pulmonary blood flow at the capillary and venular level.

VARIATIONS OF PLASMA CORTISOL AND BLOOD FIBRINOLYTIC ACTIVITY DURING ANAESTHETIC AND SURGICAL STRESS

Blood fibrinolytic activity and plasma cortisol levels were investigated during surgical procedures in twenty-three patients who underwent laparotomy. From 30 minutes to 1½ hours of surgical stress, enhancement of fibrinolysis was significantly correlated with increase of plasma cortisol levels. There were no exceptions to this pattern. The changes in fibrinolytic activity and plasma cortisol levels were found to depend mainly on the surgical stress. There was no difference with regard to the various anaesthetics employed.

Fibrinolytic Activity during Operative Procedure: Evaluation of the Measuring Method and Significance of the Changes in Fibrinolytic Activity

Fibrinolytic Activity during Operative Procedure: Evaluation of the Measuring Method and Significance of the Changes in Fibrinolytic Activity

A Study of Possible Causes of Increased Fibrinolytic Activity during Exercise

SummaryThe prolonged effect in human volunteers of brief but moderately intense exercise in enhancing fibrinolytic activity has been used to test various parameters which might have been causatively associated with the change.HMMA, venous blood glucose, body temperature and diastolic blood pressure did not alter significantly at any time. The increase in pulse rate immediately after exercise did not correlate closely with the rise in fibrinolytic activity and disappeared much sooner.Plasma cortisol and systolic blood pressure had both fallen significantly 1 hr after exercise as compared to their preexercise levels, but there was no significant inverse relationship between these parameters and the changes in fibrinolytic activity.It is concluded that the parameters measured were unlikely to be responsible for the observed changes in fibrinolytic activity.

B-2. Intracerebral Paraffin Injection and Changes in Fibrinolytic Activity of Cerebro-Spinal Fluid in Dogs

b-2. Intracerebral Paraffin Injection and Changes in Fibrinolytic Activity of Cerebro-Spinal Fluid in Dogs

DIURNAL VARIATIONS OF FIBRINOLYTIC ACTIVITY AND PLASMA-11-: HYDROXYCORTICOSTEROID LEVELS

Plasma-hydrocortisone and euglobulinlysis times have been estimated, simultaneously, at 9 A.M. and at 4 P.M. in eleven ambulant men and five bedridden patients. In both groups, plasma-hydrocortisone is lower and fibrinolytic activity significantly higher in the afternoon than in the morning. The percentage change in the fibrinolytic activity is greater in the ambulant group than in the bedridden patients. The changes in plasma-hydrocortisone and fibrinolytic activity do not seem to be causally related.

CHANGES IN FIBRINOLYTIC ACTIVITY DURING SURGICAL PROCEDURES.

CHANGES IN FIBRINOLYTIC ACTIVITY DURING SURGICAL PROCEDURES.

CHANGES IN FIBRINOLYTIC ACTIVITY PRODUCED BY PHYSICAL ACTIVITY

CHANGES IN FIBRINOLYTIC ACTIVITY PRODUCED BY PHYSICAL ACTIVITY

POSTOPERATIVE THROMBOSIS AND PLASMA FIBRINOLYTIC ACTIVITY: A Comparative Study in Africans, Indians, and Whites

Because venous thrombosis and pulmonary embolism occur so rarely in African and Indian patients a comparative study of this surgical complication was done among whites Indians and Africans in Natal. The control group was 23 Africans and 10 Indians and 11 white patients admitted for minor (nonsurgical) complaints. The patient group undergoing surgical operations consisted of 36 Africans 7 Indians and 11 whites. Blood samples were taken from patients before surgery and at various times during and after operations. Control levels of plasma fibrinolytic activity and fibrinogen were estimated. Fibrinolytic activity was approximately 2 times higher in a healthy African control (group) as it was in either the white or Indian control groups. Plasma fibrinogen levels in the 3 groups fell within accepted normal levels for white patients. During the operation there was no significant change in fibrinolytic activity in the Indian and African patients. In all 3 racial groups fibrinolytic activity decreased in the first 48 postoperative hours but rose again within 6 days postoperation. Postoperatively fibrinogen levels increased in African and white patients. These findings are difficult to correlate with the clinical reality of rare postoperative thromboembolism in the 2 racial groups; there were no cases even among whites of postoperative problems in this series.