Cilostazol was developed as a drug for reducing platelet function. The transformation of platelets on injured arterial wall is very important as a trigger of thrombus formation and creation of structural change of the arterial wall. We investigated the inhibitory effect of cilostazol on platelet adhesion using the Baumgartner's method.
In this method, circulating blood through the injured arterial wall was treated with cilostazol (10^-3, 10^-4, 10^-5M) dissolved in N, N-dimethylformamid (DMF) (0.8%). The number of adherent platelets on subendothelium and their forms (spread, contact, thrombi) were studied under light microscopy. Adherent platelets were also studied morphologically by a scanning electron microscope. The localization of β-TG in adherent platelets was studied using the ABC method.
Cilostazol reduced ‘thrombi’, but it exerted no effect on the ‘spread’ and increased the ‘contact’ platelets. On scanning electron microscopy, cilostazol also showed the reduction in platelet thrombus formation.
β-TG release from platelets seemes to be suppressed by cilostazol at the concentration of 10^-4M or above. Cilostazol seems to have the inhibitory effect on platelet thrombus formation, β-TG release and the transfomation from contact to spread.

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Canine femoral artery was substituted with expanded polytetrafluoroethylene graft (Gore-Tex) (inner diameter, 3mm) and the effect of OP-41483 α-CD (OP-41483) on the graft patency was studied at six weeks after the surgery. OP-41483 was intravenously infused at the dose of 20ng/kg/min for 3 hours two times a day. The period of administration was two weeks.
In the control group (five animals) without drug treatment, the graft patency was 40%, while all grafts were patent in the OP-41483 treated group (four animals).
The inhibitory effect of OP-41483 on platelet aggregation induced by ADP (5μM) was not observed ex vivo at the dose of 20ng/kg/min. But, the histological and electron scanning microscopic findings of the grafts showed that OP-41483 at the same dose obviously inhibited the platelet adhesion and aggregation, and this inhibitory effect might lead to elevation of the graft patency.

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Effect of PGI₂ analogue (TRK-100) on haemorheological factors in patients with peripheral vascular disease.
The effect of prostaglandin I₂ analogue (TRK-100) on haemorheological factors (red cell deformability, whole blood viscosity, plasma viscosity, and plasma c-AMP) in 12 patients with peripheral vascular disease (Buerger's disease, arteriosclerosis obliterans and Raynaud's syndrome) were studied.
Although red cell deformability was reduced in patients with peripheral vascular disease, TRK-100 (120μg/day, 6 weeks) was shown to be effective in improving the reduced red cell deformability.
However, there was no statistical change in the values of whole blood viscosity, plasma viscosity or plasma c-AMP in this study.

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Glu-plasminogen (Glu-plg) was degraded by elastase in the presence or absence of tranexamic acid. Glu-plg was degraded faster in the presence of tranexamic acid.
Increase in the concentration of tranexamic acid resulted in the increase in the appearance of degradation products, reaching a plateau level at 1mM of tranexamic acid. Fifty percent increase in the concentration of one of degradation products was obtained at 0.22mM of tranexamic acid, which is similar to a dissociation constant (Kd) of low affinity lysine binding sites (LBS) with tranexamic acid. As to the degradation rate of two isozymes of Glu-plg (Glu-plg I and II), Glu-plg II containing one carbohydrate chain was degraded faster than Glu-Plg I containing two carbohydrate chains. Comparison of the degradation rates of Glu-plg and Lys-plg indicated that Lys-pig was degraded faster.

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In patients with various thromboembolic diseases and normal subjects, plasma levels of crosslinked fibrin derivatives (XDP) were measured by a latex agglutination procedure using a new monoclonal antibody. Plasma XDP was undetectable (<1μg/ml) in all normal subjects, and in all patients with chronic arterial or venous thromboembolic diseases. It was elevated in 2 of 6 patients with acute venous thromboembolism, in 3 of 13 patients with acute arterial thromboembolism, and in all 18 patients with disseminated intravascular coagulation (DIC). In patients with DIC, XDP values correlated well with currently used FDP, and changed in parallel with the clnical course of DIC. Following the fibrinolytic therapy, plasma XDP level increased in 4 of 12 patients studied. It was suggested that this new reagent for the quantitation of XDP is useful for the assessment of secondary fibrinolysis, although it is not sensitive to mild elevation of XDP.

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Immuno-depleted protein C deficient plasma activated by activator venom from Agkistrodon contortrix (Protac^®) which is the activator of protein C showed a non-specific amidolytic activity using chromogenic substrate, S-2366. The difference of protein C amidolytic activity between the sample plasma without anti-protein C antibody and with anti-protein C antibody correlated well with the protein C antigen measured by ELISA in 22 normal subjects (r=0.9853, p<0.001). COBAS FARA spectrophotometer programed for a kinetic assay method was used in this study.
Using this method the correlations among non-specific cholinesterase (ChE), prothrombin time, thrombotest, antithrombin III activity, protein C amidolytic and anticoagulant activity, protein C antigen and vitamin K-dependent coagulation factors II, VII, IX and X activities were studied in 25 patients with liver cirrhosis. ChE correlated well with prothrombin time (r=0.8178, p<0.001), antithrombin II activity (r=0.7972, p<0.001), factor II (r=0.5550, p<0.01), factor VII (r=0.6299, p<0.001), factor IX (r=0.6379, p<0.001), factor X (r=0.5709, p<0.01), protein C antigen (r=0.7311, p<0.001), protein C amidolytic activity (r=0.7307, p<0.001) and anticoagulant activity (r=0.5504, p<0.02). From these data the level of protein C amidolytic activity and antigen indicates well the liver function of macromolecular synthesis in patients with liver cirrhosis.

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Urinary trypsin inhibitor (UTI) had strong anti-plasmin activity with synthetic amido substrate, although little activity was observed with natural fibrin substrate in the assay system. In this paper, anti-fibrinolytic properties of UTI on 11 kinds of non-plasmic enzymes were also compared. Potent inhibitions on chymotrypsin, trypsin, leukocyte protease, earthworm proteases (LR-1 and LR-2), and also a lesser extent on SH-proteases (papain and ficin) were obsereved, whereas the inhibitor showed a trace or no inhibition on LR-3, pronase, pancseas elastase or Bacillus enzyme nattokinase.
The distribution of UTI-related substances in human tissues was first examined with goat UTI-antibody. In contrast to the normal tissues having only limited immunoreactivity (kidney proximal tuble, glia, stomach, colon and bronchial cells), malignant tissues showed widely distributed reactivity, particually in that of the extracellular spaces.
Considering the molecular similarity of UTI to ECGF-2b (Mckeehan et al. 1986) and its broad inhibitry spectrum as proved now, the pathophysiological significances of UTI-related substances were suggested.

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In a previous study, we reported that levels of Blood FPA were significantly increased since the second trimester, and that of blood Bβ15-42 was significantly increased since the first trimester till the full term pregnancy. Levels of urinary FPA/CRE and Bβ15-42/CRE were found to have the same pattern as blood FPA and Bβ15-42.
These results suggested that blood FPA and Bβ15-42 were rapidly cleared into urine by glomerular filtration and hypermetabolism in the proximal tubule of the kidney. (Blood & Vessel, 19: 68-76, 1988.)
In this study, urinary levels of UK/CRE, α2-PI/CRE, α2PI-Pm-C/CRE and D-dimer were persuaded during preg., Labor and puerperium as follows.
1) UK/CRE was depressed whereas α2PI/CRE was increased markedly and α2PI-Pm-C/CRE slightly increased in 4-7 gestaional weeks.
2) UK/CRE and α2PI-Pm-C/CRE were increased slightly and α2PI/CRE decreased slightly from 8-11 weeks to 16-19 weeks.
3) UK/CRE, α2PI/CRE and α2PI-Pm-C/CRE were increased slightly and/or markedly from 20-23 weeks to 28-31 weeks, coming up to their peaks in 24-27 weeks.
4) UK/CRE was deep-depressed whereas α2PI-Pm-C/CRE was markedly increased in 32-35 weeks.
5) UK/CRE and α2PI-Pm-C/CRE were markedly increased but α2PI/CRE remained in the full them.
6) On the other hand, blood α2PI-Pm-C was markedly increased in the first trimester, but it gradually decreased from mid-term until the full term.
For these findings, it was suggested that the high levels of urinary α2PI-Pm-C/CRE during preg., labor and puerperium was attributed to rapid clearance blood through in tubule glomenular selective filtration and of matabolism.

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To determine the utility of D-dimer in the detection of left atrial thrombus in mitral stenosis (MS), we measured the plasma level of D-dimer in 23 patients who had predominant MS with or without other valvular heart diseases. The presence or absence of left atrial thrombi was confirmed at the surgery for mitral valve replacement in all cases. Left atrial thrombi were present in 10 patients (group A) and absent in 13 patients (group B). Atrial fibrillation was found in all cases.
The results were as follows;
1) The level of D-dimer was 697ng/ml (geometric mean) in group A and 101ng/ml in group B. The lowest level of D-dimer in group A was 234ng/ml and the highest one in group B was 200ng/ml. Thus, two groups were clearly separated.
2) The level of D-dimer showed a significant correlation with the weight of left artial thrombi (r=0.80, p<0.05).

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Streptokinase (SK) reacts stoichiometrically with human plasminogen and plasmin to generate plasminogen activator activity by making complex. In order to clarify the reaction of SK and plasminogen, enzymatic properties of SK were studied. Digested SK with molecular weight of 29K (SK₂₉) was prepared by tryptic digestion of native SK (nSK) with molecular weight of 47K and separated by SDS polyacrylamide gel electrophoresis. SK₂₉ was extracted from the electrophoretic gel, and its fibrinolytic and amidolytic activity was compared with that of nSK. A mixture of SK₂₉ and human plasminogen hydrolyzed only human fibrin, while a mixture of nSK and human plasminogen hydrolyzed human and bovine fibrin (Fig. 2). SK₂₉ showed the ability to activate human plasminogen in the presence of human fibrin (Fig. 3). However, different from nSK, it did not show the ability in the presence of human fibrinogen, bovine fibrin or fibrinogen. These results suggest that human fibrin formation induces comformational changes in the human plasmionogen which results in the generation of an active site by SK₂₉.

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Vitamin K (VK) deficiency associated with antibiotic therapy was been attracting the attention. It is not clearly understood it is attributable to suppression of intestinal bacterial flora or inhibition of VK reductase by N-methyl-tetrazole-thiol (NMTT) side chain in the structure of some antibiotics. In order to clarify the cause, coagulation studies were carried out with patients who had been on antibiotic therapy. The results were as follows;
1. Thrombotest (ThT) and hepaplastintest (HpT) values of patients with starvation were lower than those of patients without starvation.
2. ThT and HpT values of patients treated with antibiotics including NMTT side chain were significantly lower than those of patients with antibiotics excluding NMTT.
3. No significant difference in ThT and HpT values was observed between male and female patients treated antibiotics. However, all patients with severely decreased values of ThT and HPT were male.
4. No significant difference in ThT and HPT values was observed between the periods of antibiotic therapy less than 7 days and more than 8 days.
5. In patients treated with antibiotics including NMTT side chain, concentrations of VK families in liver were decreased compared with those in normal liver.
6. After intravenous administration of MK-4 into patients who had been on therapy of antibiotics including NMTT side chain for more than 5 days, neither MK-4 nor the epoxiade detected in their sera.

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Thrombomodulin (TM) is known to exist in the glomerulus and to be excreted in urine. To elucidate biochemical properties of urinary TM in normal and toxemic pregnancy, the levels of immunoreactive TM (TM antigen) and its activities were measured by ELISA and by a protein C activation method, respectively. The samples for measurements were prapered from urine by DIP-thrombin agarose affinity chromatography.
The urinary protein fraction bound to DIP-thrombin agarose, obtained from normal pregnants, pregnants with early onsets type toxemia (24-28 weeks of gestation), and with late onset type toxemia (later than 32 weeks) commonly showed a single band with a mol. wt. 63Kd in SDS-polyacrylamide gel electrophoresis with silver staining.
The levels of urinary TM antigen and TM activity in normal pregnancy increased with gestation weeks. Those in late onset type pregnancy showed similar chnges. There was no difference in the ratio of TM activity/antigen between these two types of pregnancy. However, in early onset type toxemia the level of TM activity was low, and, further, the ratio of TM activity/antigen was extremely low.
The TM in early onset type toxemia had a significantly lower Vmax than that in normal pregnancy. These findings suggested that the TM in early onset type toxemia was functionally impaired as a cofactor for thrombin.

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