Blood Coagulation Inhibitor in a Snake Plasma (Bothrops jararaca)

1973 ◽  
Vol 30 (01) ◽  
pp. 106-113 ◽  
Author(s):  
Linda Nahas ◽  
Ferruccio Betti ◽  
Aura S. Kamiguti ◽  
Hissae Sato
Keyword(s):  
Human Plasma ◽  
Blood Coagulation ◽  
Antithrombin Iii ◽  
The Other ◽  
Normal Human Plasma ◽  
Clotting Time ◽  
Bovine Thrombin ◽  
Heat Stable ◽  
Coagulation Inhibitor ◽  
Normal Human

SummaryExperiments with plasmas samples from the snake B. jararaca and X. merremii have shown that the two differ markedly with respect to their reaction to bovine thrombin. The plasma of X. merremii appears to react in a manner very similar to that of normal human plasma both using the thrombin clotting test and using the antithrombin III assay of Astrup and Darling (Biggs and Macfariane 1962). The plasma of B. jararaca on the other hand, contains, in addition to antithrombin III, an inhibitor which resembles mammalian heparin. This inhibitor prolongs the thrombin clotting time of human and X. merremii plasmas, is recorded by the antithrombin assay and is neutralized by protamine. The inhibitor is however, not identical with mammalian heparin since it is not adsorbed by BaSO4 and Al(OH)3 (which adsorb heparin) and it is heat labil whereas mammalian heparin is heat stable.

A Hitherto Undescribed Naturally Occurring Plasma Antagonist of Activated Factor X Inhibitor (Antithrombin III)

1979 ◽  
Author(s):  
E. T. Yin ◽  
W. J. Salsgiver ◽  
O. Tangen
Keyword(s):  
Equilibrium State ◽  
Human Plasma ◽  
Antithrombin Iii ◽  
Circumstantial Evidence ◽  
Incubation Mixture ◽  
Factor X ◽  
Normal Human Plasma ◽  
Plasma Component ◽  
Naturally Occurring ◽  
Normal Human

Circumstantial evidence suggested that normal human plasma contained a substance regulating the neutralization of F.Xa by F.Xa inhibitor(XaI), (Yin et.al.,Adv.Exper. Med. & Biol., 52 : 239, 1975, Plenum Press, N.Y.).This plasma component has now been isolated and partially purified in our laboratory, and tentatively designated as “Anti-XaI”.In experiments employing purified components, when Anti-XaI was incubated at 37°C with F.Xa, Xal and heparin for two minutes at pH7.5, the amount of F.Xa inhibited was inversely proportional to the Anti-XaI concentration. But, when the F.Xa was replaced by thrombin in the incubation mixture, the neutralization of thrombin clotting activity was undisturbed.Anti-XaI was found to be neither PF3 nor PF4.These and other data strongly suggest that the “Antithrombin III pathway” is more complex than currently believed to be. In circulating blood an equilibrium state must exist between Anti-XaI and XaI.Under certain conditions when the Anti-XaI activity is predominant the rate of F.Xa neutralization bv XaI then becomes slower than the activation of prothrombin to thrombin by F.Xa.

Studies on the Nature of the Plasma Erythropoietic Factor(s)

PEDIATRICS ◽  
1958 ◽  
Vol 21 (4) ◽  
pp. 581-581
Keyword(s):  
The Other ◽  
Normal Human Plasma ◽  
Erythropoietic Activity ◽  
Cellular Division ◽  
Humoral Factors ◽  
Hemoglobin Variability ◽  
Heat Stable ◽  
Hemopoietic Tissue ◽  
Blood Formation ◽  
Normal Human

In recent years the existence of a humoral factor or factors which stimulate erythropoietic activity has been demonstrated. The present paper reports further studies on the nature of this erythropoietic factor or factors. The author's studies indicate that there are at least two humoral erythropoietic facts. One is heat stable and appears to exert its effects upon cellular division of erythrocyte precursers in the marrow. The other factor is relatively thermolabile and exerts its effect through augmentation of incorporation of iron into hemoglobin. Variability in experimental results which have been reported in studies of the humoral erythropoietic factor may, in the authors' opinion, be due to differences in the material being studied (in content of these factors depending upon how the material being tested was prepared). These humoral factors are present in normal human plasma which suggests that they are involved in the maintenance of normal blood formation. Increased amounts of these factors in plasma in some anemias may be the result of local tissue hypoxia. In polycythemia vera the humoral factors may be of pathogenetic importance. The factors do not appear to be formed in hemopoietic tissue; the kidney has been suggested as a possible locus of formation.

The Determinant of the Prothrombin Time in Normal Human Plasma

1958 ◽  
Vol 02 (03/04) ◽  
pp. 226-235 ◽  
Author(s):  
Armand J. Quick
Keyword(s):  
Prothrombin Time ◽  
Human Plasma ◽  
Active State ◽  
The Other ◽  
Normal Adult ◽  
Normal Human Plasma ◽  
Prolonged Prothrombin Time ◽  
Adult Human ◽  
Plasma Factor ◽  
Normal Human

SummaryNormal adult human plasma has a constant prothrombin time when determined under standardized conditions and with carefully prepared reagents. An explanation for this constancy is offered; namely, that a plasma factor, designated as “prothrombin time fixing agent” (PTFA), is responsible for maintaining a constant fraction of the total prothrombin in the active state. This fraction is measured quantitatively by the prothrombin time, while the inactive prothrombin or prothrombinogen, has no influence on the test. The concentration of PTFA is fixed by heredity and appears to be a dominant. The results of studies on two subjects, one with true hypoprothrombinemia, the other with a prolonged prothrombin time but a normal total prothrombin and no deficiency of accessory prothrombin factors are reported and interpreted according to this hypothesis. A deficiency of PTFA can be differentiated from all other known hypoprothrombinemic states by observing a prolonged prothrombin time when mixing the plasma with an equal volume of fresh normal plasma.

Relative Importance Of Plasma Protease Inhibitors In The Inactivation Of Kallikrein In Human Plasma

1981 ◽  
Author(s):  
M Schapira ◽  
C F Scott ◽  
R W Colman
Keyword(s):  
Human Plasma ◽  
Antithrombin Iii ◽  
Plasma Concentrations ◽  
The Other ◽  
High Molecular Weight Kininogen ◽  
Physiological Conditions ◽  
First Order ◽  
Complete Inactivation ◽  
Important Regulator ◽  
Normal Human

Human plasma contains several inhibitors of plasma kallikrein (KAL), including C1-inhibitor (C1INH), α2-macro- globulin (α2M), antithrombin III (ATIII), and α1-antitrypsin (αlAT). Studies in purified systems have allowed us to quantitate the kinetic constants of each isolated inhibitor. We also have demonstrated that high molecular weight kininogen (HMWK) is an important regulator since it decreases the inactivation rate of KAL by all inhibitors except α2M. When purified inhibitors and HMWK are present at plasma concentrations, it can be calculated that C1INH, α2M, ATIII and α1AT account respectively for 49%, 49%, 0.8% and 0.2% of the KAL inhibitory activity. To assess if this prediction derived from purified system adequately describes the inhibition of KAL under more physiological conditions, we incubated KAL with normal human plasma (NHP), C1INH-deficient plasma (C1INH-D), and α2M-deficient plasma (α2M-D). KAL activity_was assessed using H-D-Pro-Phe-Arg- Nan as a substrate. C1INH-D was obtained from a patient with hereditary angioedema. C1INH in C1INH-D was 15% of the normal value as assessed by radial immunodiffusion. α2M-D was obtained by selective and complete inactivation of α2M by methylamine. The pseudo-first-order rate constants for the inactivation of_KAL by NHP, C1INH-D, α2M-D, and plasma deficient in both C1INH and α2M were respectively 8.8, 5.0, 5.5, and 1.8 S-1(×l03). Therefore, C1INH accounted for 63% of the observed inhibition, α2M for 35%, and all the other inhibitors for 2%. When these values were corrected for the concentration of HMWK, C1INH accounted for 47% of the inhibition, α2M for 51%, and all the other inhibitors for <2%. Thus, there is an excellent agreement between the results obtained when KAL is inhibited in purified systems and those obtained when it is inhibited in plasma. Moreover, these results indicate that C1INH and α2M are the only important inhibitors of KAL in NHP.

scholarly journals Human antithrombin III heterogeneity

Blood ◽  
1981 ◽  
Vol 57 (2) ◽  
pp. 229-232 ◽  
Author(s):  
L Williams ◽  
G Murano
Keyword(s):  
Human Plasma ◽  
Antithrombin Iii ◽  
Agarose Gel ◽  
Normal Human Plasma ◽  
Congenital Deficiency ◽  
Single Donor ◽  
At Iii ◽  
Normal Human

Abstract Crossed immunoelectrophoretic patterns were obtained on three patients with a congenital deficiency of anti-thrombin III (AT-III), and on normal single donor and “pooled” plasma controls. In the presence of heparin (incorporated into the agarose gel matrix), the AT-III of normal human plasma was separated into four components: two major, faster-moving components, and two minor, slower-moving components. The three patients with congenital deficiency of AT-III (levels approximately 50% of normal) appeared to possess only one of the faster- moving components, and one of the slower-moving components.

A Hitherto Undescribed Naturally Occurring Plasma Antagonist of Activated Factor X Inhibitor (Antithrombin III)

1979 ◽  
Author(s):  
E.T. Yin ◽  
W.J. Salsgiver ◽  
O. Tangen
Keyword(s):  
Equilibrium State ◽  
Human Plasma ◽  
Antithrombin Iii ◽  
Circumstantial Evidence ◽  
Incubation Mixture ◽  
Factor X ◽  
Normal Human Plasma ◽  
Plasma Component ◽  
Naturally Occurring ◽  
Normal Human

Circumstantial evidence suggested that normal human plasma contained a substance regulating the neutralization of F. Xa by F. Xa inhibitor (XaI), (Yin et.al., Adv. Exper. Med.& Biol., 52: 239, 1975, Plenum Press, N.Y.).This plasma component has now been isolated and partially purified in our laboratory, and tentatively designated as “Anti-Xal”.In experiments employing purified components, when Anti-Xal was incubated at 37°C with F. Xa. Xal and heparin for two minutes at pH7.5, the amount of F. Xa inhibited was inversely proportional to the Anti-XaI concentration. But, when the F. Xa was replaced by thrombin in the incubation mixture, the neutralization of thrombin clotting activity was undisturbed. Anti-Xa I was found to be neither PF3 nor PF6.These and other data strongly suggest that the “Antithrombin ill pathway” is more complex than currently believed to be. In circulating blood an equilibrium state must exist between Anti-Xal and Xal. Under certain conditions when the Anti-Xal activity is predominant the rate of F.Xa neutralization by Xal then becomes slower than the activation of prothrombin to thrombin by F.Xa.

scholarly journals Human antithrombin III heterogeneity

Blood ◽  
1981 ◽  
Vol 57 (2) ◽  
pp. 229-232
Author(s):  
L Williams ◽  
G Murano
Keyword(s):  
Human Plasma ◽  
Antithrombin Iii ◽  
Agarose Gel ◽  
Normal Human Plasma ◽  
Congenital Deficiency ◽  
Single Donor ◽  
At Iii ◽  
Normal Human

Crossed immunoelectrophoretic patterns were obtained on three patients with a congenital deficiency of anti-thrombin III (AT-III), and on normal single donor and “pooled” plasma controls. In the presence of heparin (incorporated into the agarose gel matrix), the AT-III of normal human plasma was separated into four components: two major, faster-moving components, and two minor, slower-moving components. The three patients with congenital deficiency of AT-III (levels approximately 50% of normal) appeared to possess only one of the faster- moving components, and one of the slower-moving components.

scholarly journals STUDIES IN BLOOD COAGULATION: THE COAGULATION PROPERTIES OF CERTAIN GLOBULIN FRACTIONS OF NORMAL HUMAN PLASMA IN VITRO12

1945 ◽  
Vol 24 (5) ◽  
pp. 698-703 ◽  
Author(s):  
F. H. L. Taylor ◽  
C. S. Davidson ◽  
H. J. Tagnon ◽  
M. A. Adams ◽  
A. H. MacDonald ◽  
...  
Keyword(s):  
Human Plasma ◽  
Blood Coagulation ◽  
Normal Human Plasma ◽  
Normal Human

Plasma Inhibition of the Heparin Accelerated Neutralisation of Xa by Antithrombin

1979 ◽  
Author(s):  
I.R. MacGregor ◽  
D.A. Lane ◽  
V.V. Kakkar
Keyword(s):  
Human Plasma ◽  
Synthetic Peptide ◽  
Antithrombin Iii ◽  
Coagulation Factors ◽  
Normal Human Plasma ◽  
Platelet Factor ◽  
Peptide Substrates ◽  
Normal Human ◽  
Heparin Fractions ◽  
Inhibition Of Thrombin

The ability of heparin fractions of different MW (mean MW 8500-30,000) to potentiate the action ot antithrombin III against the coagulation factors thrombin and Xa has been examined in purified reaction mixtures and in plasma. Residual thrombin and Xa have been determined by their peptidase activities against the synthetic peptide substrates H-D-Phe Pip-Arg-pNA and Bz-Ile-Glu-Gly-Arg-pNA. High MW heparin fractions were found to have higher anticoagulant activities than low MW heparin when studied with both thrombin and Xa incubation mixtures in purified mixtures. The inhibition of thrombin by heparin fractions and antithrombin III was unaffected by other plasma components. However, normal human plasma contained a component that inhibited the heparin and antithrombin III inhibition of Xa, particularly when the high MW heparin fraction was used. Experiments using a purified preparation of platelet factor 4 suggested that this platelet derived heparin neutralising protein was not responsible for the inhibition and that a hitherto undescribed inhibitor of heparin action is present in plasma. Preliminary studies have indicated that the inhibitor is concentrated in a fraction rich in lipoprotein and obtained by ultracentrifugation of plasma in high density salt.

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