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Since the single factor activity of the cat differed in part distinctly from humans (factor II: 94%, factor V: 500%, factor VII: 125%, factor X: 62%) the method had to be optimized, above all to exclude an influence of a reactive increased factor V-activity on the results of the other coagulation factors. Dilution series of cat pool plasma (CPP) (n = 50 cats) showed, that a commercial human placenta thromboplastin was more suitable as activating reagent than rabbit brain thromboplastin. Using the required sample predilution (1:40), measurements with the latter reagent were more precise when measured on the relation between the imprecision and the time interval between different CPP-dilution steps. Reference curves were prepared for CPP using the optimized method and human placenta thromboplastin (50 microliters 1:40 prediluted sample and 50 microliters deficient plasma were incubated at 37 degrees C for 1 minute, addition of 200 microliters Ca-thromboplastin) and reference ranges were calculated using the values of 57 cats (factor II: 74-126%, factor V: 42-184%, factor VII 56-150%, factor X: 65-143%).

The activity of the coagulation factors II, V, VII and X was measured in plasmas of 167 healthy dogs of different age, sex and breeds using a test optimized for dogs. During the first months of life particularly the factor X-activity, but also the activity of factor-II-, and by way of suggestion the factor V-activity was lower in comparison to adult dogs. A dependence on the sex was only seen for the factor II- (p = 0.0497) and V-activity (p = 0.0467), which was slightly higher in not castrated female than in male dogs. Significant differences between different breeds existed for factor VII. With regard to a collective of different breeds the reference values (2.5- and 97.5%-quantile) were calculated for adult dogs (n = 111). Especially the range of the factor VII- (62-180%), and also of factor V-activity (68-137%) was wider than that of the factor II- (84-126%) and factor X-activity (77-121%).

The pharmacokinetics of racemic phenprocoumon were studied in 8 adult horses after the single intravenous and oral administration of 0.75 mg/kg. After i.v. administration the plasma concentration of phenprocoumon showed a biphasic decline in time. The pharmacokinetics were calculated on the two-compartment open model. The average plasma half-life (beta-phase) was 22 hours, the apparent volume of distribution was 0.61 l/kg, Cltot was 25.2 ml/kg/h (13.9-40.9 ml/kg/h). The systemic bioavailability of oral phenprocoumon was 97.6%, Tmax was found to be 4-12 hours. The effect of phenprocoumon on the coagulation system was determined by the activity of Factor X, the Quick's one stage prothrombin time and the PTT. Factor X showed the most marked effect. A reduction of the content of Factor X was seen over 7-9 days, it decreased to 11-33%. Quick's one stage prothrombin time was reduced over 4-8 days, the lowest values were 22-55%. The PTT showed only a small reaction on the single administration of 0.75 mg/kg phenprocoumon. Differences in the effect on the coagulation between the i.v. and the oral administration could not be observed. In comparison to warfarin, phenprocoumon showed a longer t0.5 (beta) and produced a markedly longer hypothrombogenic reaction. Therefore phenprocoumon appeared to be more suitable for a long term anticoagulation therapy in horses than the structurally related warfarin.

Following clotting factor assays were performed on the fluid of burn blisters of 11 patients with severe burns: Fibrinogen levels, Factor II, V, X and XIII, thrombin time, fibrin split products, plasminogen, antithrombin III, IgA, IgM, IgG, ethanol gelation test and total proteins. The results showed, that a quantity of Factor II, X and XIII, antithrombin III, plasminogen and IgG had left the circulation. On the contrary we found only small concentrations of Factor V, fibrinogen, IgM and IgA in the fluid of burn blisters. This distribution suggested that the losses of plasma proteins into the burn blisters were correlated to their concentration and their molecular weight. The decrease of plasma coagulation proteins during the first days after severe burns was probably partly due to losses through the walls of the vessels, because of the increased capillary permeability.

32 overweight otherwise healthy children aged 8-15 years received a hypocaloric mixed diet for some weeks. Their blood coagulation was studied with regard to possible changes. Before dieting the levels of fibrinogen were markedly increased, also maximal amplitude (ma) of the thrombelastograms. The other values were within the normal range. During the diet statistically significant changes were found in the values of the following coagulatin parameters: ma of the thrombelastograms as well as the activities of the coagulation factors I, II, VII, VIII, IX, and X.

The amidolytic activities of plasma generated by means of thromboplastin and Ca++, on the one hand, and by means of partial thromboplastin, a contact activator and Ca++, on the other hand, were determined using synthetic, chromogenic factor Xa substrates with low affinity for thrombin (CH3SO2-D-Leu-Gly-Arg-pNA and CH3SO2-D-Nleu-Gly-Arg-pNA). In this way, the activation process by splitting off the p-nitroaniline was followed. Besides the summary detection of factor Xa was obtained after addition of hirudin. During preincubation with partial thromboplastin and contact acti (Actin) in Ca++-free medium, an amidolytic activity so far unidentified was generated that renders evaluation of the activation process difficult. In the test system with partial thromboplastin, factor Xa could not be determined and the thrombin-like activity that can be inhibited by hirudin did not correspond to the amount of prothrombin present in plasma. In contrast, activation of factor X and prothrombin by thromboplastin and Ca++ could be followed and the content of the two zymogenes could be detected simultaneously. In general, under optimized reaction conditions, automated systems might be developed that would provide additional diagnostic information about determination of clotting time, on the one hand, and about quantitative determination of zymogen, on the other hand.

Since monitoring of oral anticoagulation (OA) by prothrombin time (PT) is a source of standardization difficulties, the authors have tested another approach. 107 patients under long term OA were monitored by both PT and a colorimetric factor X assay (in vitro activation of factor X with RVV and assessment of amidolytic activity towards S-2222). The PT values were between 10 and 34% (therapeutic range 15--25%), and factor X levels were between 10 and 44% (therapeutic range 16--24%). The correlation between the two methods was highly significant (r = 0.65, p less than 0.001). In 68% of the patients the two tests gave the same information (55 subjects were adequately, 16 insufficiently and 2 over-anticoagulated). For a slightly broader therapeutic range (PT 15--30%, corresponding to 16--28% factor X) concordant information was obtained in 82% of the patients. During stable OA, PT and factor X assay gave very similar information. An advantage of the latter method is the possibility of automation, while a disadvantage is its insensitivity to factor VII.

45 rabbits of both sexes were divided into five groups. Animals were sham irradiated, inflicted with an autologous haematoma as a trauma, whole-body irradiated with 500 RX-rays, and inflicted with a combination of irradiation and autologous haematoma or skin-wound. Already 24 hr after irradiation a highly significant prolongation of the activated partial thromboplastin-time was observed. The concentrations of factor X and fibrinogen increased in all irradiated animals 24 hr after irradiation. Following the combination injury of irradiation and skin-wound such increases were significantly higher than those after irradiation alone. The activities of antithrombin III and antiplasmin, measure with chromogen substrates, rose after irradiation as well as after combined injuries. In spite of the increased level of fibrinogen we could register hypocoagulability with significant increase of activation as well as of inhibition of the plasmatic coagulation system 24 hr after combined injuries.

Methods are described for the determination of the thromboplastin time, the thrombin time, for fibrinogen and factor II, V and X from capillary blood. These methods are easy to perform and comparison of the results from venous and capillary blood showed a very good correlation. The described methods seem suitable for routine coagulation tests in pediatrics.

The influence of venous occlusion on plasmatic coagulation, on platelets, and on fibrinolysis was examined. After occlusion, activated factors XI and X could be demonstrated. Simultaneously, platelet aggregation induced by both collagen and epinephrine was increased. Fibrinolysis was found to be moderately enhanced. In patients taking acetylsalicylic acid (ASA), platelet functions were not altered by occlusion but the activation of plasmatic clotting factors was not influenced. Low dose heparin inhibited plasmatic activation but had no influence on the increase of platelet activities. By simultaneous administration of both substances, an additive effect was observed resulting in inhibition of plasmatic and platelet activation due to venous occlusion.

Polyamino-polycarboxyl acids (ampholines) used for electrofocusing have the effect of shortening the coagulation time during the one stage test, which is in direct proportion to the activity of factor VIII already present. Compared with factor VIII, ampholine 5-7 and 7-10 have a different range of effect as far as their stimulating activity is concerned. For increasing their activity a minimum PPCS concentration of 0.1 m Mol/l is required in the test run. There is no own effect of these substances similar to factor VIII. The activity of factor IX and X is not influenced. Ampholines gained from acrylic acid and ethylenediamine will not enhance the activity of factor VIII in the course of the one stage test.