Blood Coagulation In Rats Research Articles

The hypocoagulant effect of Crataegus aronia in rats entails vitamin K-dependent and vitamin K-independent effects.

This study investigated the effect of the aqueous extract of Crataegus aronia on blood coagulation in rats. Rats (200±10g,) were divided into two groups (6 rats/each) of control or C. aronia-treated rats which treated with the vehicle or the extract (200mg/kg) for 21days. With normal liver structure, serum levels of ALT, AST and ɣ-GT, platelet count, and plasma levels of vWF, values of PT and aPTT were significantly increased in C. aronia-treated rats. Also, it lowered serum levels of vitamin K (VK) and plasma activities of FII, FV, FVII, FVIII, FIX, FX, and FXI and downregulated hepatic levels of the VK-dependent factors (FII, FVII, FIX, and FX). In addition, C. aronia reduced fecal levels of triglycerides and cholesterol and serum levels triglycerides, cholesterol, LDL-c, and vLDL-c. In conclusion, with the hypocoagulant effect of C. aronia activity involves VK-dependent and non-vitamin K-dependent factors. PRACTICAL APPLICATIONS: In this study, we are reporting for the first time an in vivo hypocoagulant effect of C. aronia in rats. Such effect involved both VK-dependent and independent factors. However, the decrease in the activity and expression of VK-dependent factors was associated with reduced fecal levels of TGs and CHOL and serum levels of TGs, CHOL, LDL-c, and vLDL-c. These data suggest a possible impairment in the VK absorption, transport, or hepatic uptake. These data encourage further pharmacological, translational, and clinical studies to isolate the active ingredients to investigate them at the human level.

Significant inhibition of the triggering mechanism of the extrinsic system of blood coagulation in rats by thymus peptides thymulin, thymosin alpha 1 and thymosin beta 4

INTRODUCTION : The role of the thymus gland and the effects of thymic peptides on the coagulation status are relatively insufficiently studied. Recent data indicate controversial and not persuasive results due to in­vestigation of single hemostasis parameters and application of various pathological models. AIM : The present study aimed to elucidate the influence of thymus peptides thymulin, thymosin alpha 1 and thymosin beta 4 applied s.c. on intact rats, on key triggering factors of blood coagulation via the extrin­sic pathway: plasma concentration of tissue factor (TF); concentration and activity of free TFPI; and the ac­tivity of plasma clotting factor VII, as well as on prothrombin time (PT) - an integral clinical parameter of the intrinsic pathway. MATERIALS AND METHODS : The study was performed on 52 male Wistar strain rats, weighing 200-220 g and bred under standard conditions at dark/light cycle 12/12 h. The rats were divided into four equal groups (n=13) and injected s.c. once daily in the time interval 08.00-09.00 h in the course of three consecutive days as follows: 1st group (controls) - with saline (the solvent of the peptides); 2nd group - with thymulin (Sigma Aldrich, 0.4 mg/kg b.m.); 3rd group - with thymosin alpha 1 (Sigma Aldrich, 0.3 mg/kg b.m.); and the 4th group - with thymosin beta 4 (Sigma Aldrich, 0.3 mg/kg b.m.). RESULTS : Results indicate that thymulin and thymosin alpha 1 expressively decrease TF and increase TFPI concentrations. All three thymic peptides reduce FVIIa activity, increase TFPI activity, and significantly elongate PT. CONCLUSIONS : Thymus peptides thymulin, thymosin alpha 1 and thymosin beta 4 significantly suppress blood coagulation through the extrinsic pathway and generate a distinct tendency for hypocoagulability.

О физиологических механизмах действия секретов слюнных желез клещей Argas persicus Oken, 1818 (Argasidae, Argas)

The anticoagulant effect of salivary secretion of ticks Argas persicus was studied. The experiments were conducted on aorta preparations isolated from the chest of white outbread rats. Isometric contraction in an isolated muscle preparation was registered by mechanotron. To determine the anticoagulant mechanism of blood plasma at deficiency of factors X, XI, IX and VIII we used the activated partial thromboplastin time. It was determined that the process of blood coagulation in rats slows down. The coagulation values depend on the concentration of tested secretions. It was found that at concentration 150 mkg /ml, the blood coagulation rate fell to 78,4 %. The role of calcium ions in regulation of vascular smooth muscle cells (VSMCs) contraction was determined. The components of salivary glands A. Persicus have a relaxation effect on the contraction of rat aortic ring preparation.

The involvement of ginseng berry extract in blood flow via regulation of blood coagulation in rats fed a high-fat diet

BackgroundThe present study investigated the effect of ginseng berry hot water extract (GBx) on blood flow via the regulation of lipid metabolites and blood coagulation in rats fed a high-fat diet (HFD). MethodsSixty rats were divided into five groups in descending order of body weight. Except for the control group, the other four groups were fed a HFD containing 45% kcal from fat for 11 wk without GBx. GBx groups were then additionally treated by gastric gavage with GBx dissolved in distilled water at 50 (GBx 50) mg/kg, 100 (GBx 100) mg/kg, or 150 (GBx 150) mg/kg body weight for 6 wk along with the HFD. To investigate the effects of GBx on rats fed a HFD, biochemical metabolite, blood coagulation assay, and histological analysis were performed. ResultsIn the experiments to measure the serum levels of leptin and apolipoprotein B/A, GBx treatment attenuated the HFD-induced increases in these metabolites (p < 0.05). Adiponectin and apolipoprotein E levels in GBx-treated groups were significantly higher than the HFD group. Prothrombin time and activated partial thromboplastin time were increased in all GBx-treated groups. In the GBx-treated groups, the serum levels of thromboxane A2 and serotonin were decreased and concentrations of serum fibrinogen degradation products were increased (p < 0.05). Moreover, histomorphometric dyslipidemia-related atherosclerotic changes were significantly improved by treatment with GBx. ConclusionThese results suggest the possibility that GBx can ameliorate blood flow by decreasing intima-media thickness via the regulation of blood coagulation factors related to lipid metabolites in rats fed a HFD.

A Novel Model of Burn-Blast Combined Injury and Its Phasic Changes of Blood Coagulation in Rats

Burn-blast combined injury has a complex pathological process that may cause adverse complications and difficulties in treatment. This study aims to establish a standard animal model of severe burn-blast combined injury in rats and also to investigate early phasic changes of blood coagulation. By using 54 Wistar rats, distance from explosion source (Hexogen) and size of burned body surface area were determined to induce severe burn-blast combined injury. Thereafter, 256 rats were randomly divided into four groups (n = 64): blast injury group, burn injury group, burn-blast combined injury group, and sham injury group. Gross anatomy and pathological changes in lungs were investigated at 3, 24, 72, and 168 h, respectively. Blood was also collected for analyzing coagulation parameters as prothrombin time, activated partial thromboplastin time, and plasma levels of fibrinogen, D-dimer, antithrombin III, and α2-antiplasmin from 0 to 168 h after injury. Severe burn-blast combined injury was induced by inflicting rats with a moderate blast injury when placing rats 75 cm away from explosion source and a full-thickness burn injury of 25% total body surface area. The rats with burn-blast combined injury had more severe lung injuries when compared with the other three groups. Pathological examination in the BBL group showed diffused alveolar hemorrhage, fluid filling, alveolar atelectasis, rupture and hyperplasia of partial alveolar septum, emphysema-like change, reduced capillary bed, and infiltration of extensive polymorphonuclear cells after injury. The blood of combined injured rats was in a hypercoagulable state within 24 h, shortly restored from 24 to 48 h, and rehypercoagulated from 48 to 72 h after injury. A secondary excessively fibrinolytic function was also found thereafter. The rat model of burn-blast combined injury was successfully established by simulating real explosion characteristics. Rats with burn-blast combined injuries suffered from more severe lung injuries and abnormal coagulation and fibrinolytic function than those induced by a burn injury or a blast injury component. Hence, a time-dependent treatment strategy on coagulation function should be emphasized in clinical therapy of burn-blast combined injury.

The biological activity and tissue distribution of 2',3'-dihydrophylloquinone in rats.

2',3'-Dihydrophylloquinone (dihydro-K1) is a hydrogenated form of vitamin K1 (K1), which is produced during the hydrogenation of K1-rich plant oils. In this study, we found that dihydro-K1 counteracts the sodium warfarin-induced prolonged blood coagulation in rats. This indicates that dihydro-K1 functions as a cofactor in the posttranslational gamma-carboxylation of the vitamin K-dependent coagulation factors. It was also found that dihydro-K1 as well as K1 inhibits the decreasing effects of warfarin on the serum total osteocalcin level. In rats, dihydro-K1 is well absorbed and detected in the tissues of the brain, pancreas, kidney, testis, abdominal aorta, liver and femur. K1 is converted to menaquinone-4 (MK-4) in all the above-mentioned tissues, but dihydro-K1 is not. The unique characteristic of dihydro-K1 possessing vitamin K activity and not being converted to MK-4 would be useful in revealing the as yet undetermined physiological function of the conversion of K1 to MK-4.

Dexamethasone induced alterations in the levels of proteases involved in blood pressure homeostasis and blood coagulation in rats.

This study was designed to investigate the alterations in the levels of various proteases such as angiotensin converting enzyme (ACE), kallikrein, aminopeptidases, urokinase and plasmin in serum-heart and kidney and to find out whether the changes in the levels of these enzymes could explain the pathogeneses of hypertension induced by Dexamethasone (Dex). Dex was administered to Male Wistar rats (180-200 g body weight) at a dosage of 2.5 mg/kg/week subcutaneously on alternate days for 2 weeks. One more week was included in this investigation to oversee the recovery process. Mean Arterial Pressure (MAP) showed significant elevation during administration and after withdrawal of Dex. The levels of enzymes such as angiotensin converting enzyme, carboxypeptidase-N and leucine aminopeptidase were found to be elevated in serum as well as in tissues. The level of kallikrein was observed to decrease in serum and tissues and that of thrombin, plasmin and urokinase exhibited variations. Thus, treatment with Dex altered the levels of these proteases which might have a role in the pathogenesis of hypertension and in altered blood coagulation.

Comparison of intestinal absorption of vitamin K 2 (menaquinone) homologues and their effects on blood coagulation in rats with hypoprothrombinaemia

To examine the physiological activities of vitamin K 2 (menaquinone, MK) homologues with different numbers of isoprene units, MK with 1–14 isoprene units and menadione (MK-0) were administered to rats with hypoprothrombinaemia, and the absorption, concentration in liver and ameliorating effect of these MK on hypoprothrombinaemia were compared. Hypoprothrombinaemia was induced by giving a vitamin K-deficient diet and warfarin (0.06 mg/kg body weight) for 8 days. Before MK treatment, the MK were undetectable in plasma and liver. At 6 hr after oral MK administration (0.1 mg/kg): MK was not detected in the plasma in rats treated with MK with 1, 2, 3 or more than 12 isoprene units; the MK level in the liver was increased but blood coagulation activity was not improved in rats treated with MK with 0, 9, 10 or 11 isoprene units; the MK level in the liver was increased and hypoprothrombinaemia was slightly improved in rats treated with MK with 7 or 8 isoprene units; and the MK level in the liver was increased and hypoprothrombinaemia was markedly improved in rats treated with MK with 4, 5 or 6 isoprene units. Almost identical results were observed 3 hr after intravenous injection of MK with 4, 5 or 6 isoprene units (10 nmol/kg). These findings suggest that the number of isoprene units of MK is an important factor in its absorption and incorporation into the liver and that the ameliorating effect of MK on hypoprothrombinaemia does not parallel their concentrations in the liver.

The dose-dependent effect of BHT (butylated hydroxytoluene) on vitamin K-dependent blood coagulation in rats

Earlier studies have reported a reduction of vitamin K-dependent blood clotting factor activity and incidence of haemorrhagic death in rats fed butylated hydroxytoluene (BHT); however, the vitamin K status of the animals used in these studies was claimed to be inadequate. The aim of the study reported here was to determine the effect of BHT on vitamin K-dependent clotting factors in vitamin K-sufficient and vitamin K-supplemented rats. Rats given BHT (3000 mg/kg body weight) for up to 21 days, in a diet containing a minimum of 3 ppm vitamin K 3 (six times the recommended requirement), showed decreased vitamin K-dependent blood clotting factor activities, demonstrated by increases in factor-specific clotting time assays. Clotting times were prolonged within 7 days, significantly increased within 14 days ( P < 0.001) and maximally increased 5.5-fold at 21 days ( P < 0.05). Supplementation with a further 250 ppm vitamin K 3 reversed this effect. BHT did not increase prothrombin time (PT), the usual index of clotting. However, in a similar 14-day investigation, a small but significant increase in PT (up to 151%, P < 0.005) was seen within 7 days. Further vitamin K supplementation was incapable of reversing this effect completely. A similar trend was shown by activated partial thromboplastin time. The 1/51 dilution Thrombotest, a more sensitive indicator of vitamin K-dependent clotting factor activity in the rat, was significantly increased (more than four fold, P < 0.01) within 7 days. This increase was fully reversed by further vitamin K supplementation. Prolongation of Thrombotest time was significant at a BHT dose level of 600 mg/kg body weight per day and this could be reversed by further supplementation of only 3.0 ppm vitamin K. However, at dose levels of 125 mg BHT/kg body weight per day or less, no clotting defects were observed. These studies confirm that chronic administration of more than 600 mg BHT/kg/day to rats supplied with recommended amounts of vitamin K can depress clotting factors and precipitate haemorrhagic deaths. When further vitamin K is provided, these deaths could be prevented even though not all clotting abnormalities may be reversed. This study disproves the proposal that BHT-related clotting factor defects are confined to rats of inadequate vitamin K status, but shows that such effects do not occur at dose levels lower than 600 mg/kg/day. The results further indicate that rats receiving a high dose of BHT have a higher vitamin K requirement than would otherwise be considered necessary. However, as BHT produces no clotting defects in these animals receiving an intake 1000 times the acceptable daily intake, such clotting effects are most unlikely to indicate a human safety problem for BHT.

Anticoagulant activity of ilexoside D, a triterpenoid saponin fromIlex pubescens

The anti-coagulant activity of ilexoside D isolated from the roots ofIlex pubescens Hook. et Arn. was investigated inin vivo andin vitro models of blood coagulation in rats. On oral administration, ilexoside D prolonged the bleeding time and the whole blood recalcified clotting time, but not the plasma recalcified clotting time.In vitro, ilexoside D did not affect the recalcified clotting times of whole blood, platelet-rich plasma (PRP), and platelet-poor plasma (PPP) while in the presence of tissue factor the compound prolonged the reduced prothrombin times of whole blood, PRP and PPP in the dose-dependent manner. These results indicate that ilexoside D has the anti-tissue factor activity as well as the antithrombotic activity.

Effect of TRK-100, a prostacyclin analogue, on endotoxin-induced enhancement of blood coagulation in rats.

TRK-100 (0.03, 0.1 and 0.3 mg/kg, p.o.), a chemically stable analogue of prostacyclin, dose-dependently prevented blood coagulation and glomerular fibrin deposition which were enhanced by 4 hr infusion of endotoxin (100 mg/kg) in rats. In addition, TRK-100 suppressed the generation of endotoxin-induced tissue thromboplastin like activity in cultured human endothelial cells.

Effect of TRK-100, a Prostacyclin Analogue, on Endotoxin-Induced Enhancement of Blood Coagulation in Rats

TRK-100 (0.03. 0.1 and 0.3 mg/kg. p.o.), a chemically stable analogue of prostacyclin, dose-dependently prevented blood coagulation and glomerular fibrin deposition which were enhanced by 4 hr infusion of endotoxin (100 mg/kg) in rats. In addition, TRK-100 suppressed the generation of endotoxin-induced tissue thromboplastin like activity in cultured human endothelial cells.

Effect of sympathectomy on platelet aggregation and blood coagulation in rats.

It is shown that the ability of blood platelets to aggregate in partially and completely sympathectomized rats is significantly lower than in intact animals. The blood clotting system of sympathectomized rats is hyperactive. The sympathectomy-provoked changes may be due to the increased content of adrenaline in the blood.

The effect of allylisothiocyanate and other antithyroid compounds on blood coagulation in rats

The effect of allylisothiocyanate and other antithyroid compounds on blood coagulation in rats

Effects of S-8527 (1, 1-BIS [4’-(l”-Carboxy-L”-Methylpropoxy) Phenyl] Cyclohexane), A New Hypolipidemic Compound, on Platelet Aggregation, Adhesiveness and Blood Coagulation in Rats

Effects of S-8527 (1, 1-bis [4’-(l”-carboxy-L”-methylpropoxy) phenyl] cyclohexane) on platelet aggregation, adhesiveness and blood coagulation were examined in rats. In animals maintained on a semisynthetic diet containing sucrose (62%) as the only carbohydrate source, platelet adhesiveness increased as compared with that in rats fed a normal chow pellet. Under these experimental conditions, oral dose of S-8527 (30–300 mg/kg) for 14 days decreased platelet adhesiveness and ADP-induced platelet aggregation, but did not decrease collagen-induced platelet aggregation. S-8527 also showed a slight but significant increase of R value of thrombelastograph. In rats which were fed a normal chow pellet oral dose of S-8527 for 14 days did not significantly affect the several tests of platelet function and blood coagulation. These results suggest that S-8527 normalizes the platelet function in a hyper-adhesive state, but does not affect the platelet function in a normal state.

BLOOD COAGULATION DISTURBANCES DUETO BENZANTHRONE

The effect of benzanthrone (an anthraquinone derivative) on blood coagulation in rats has been investigated. Coagulation time, plasma fibrinogen, platelets, pro-thrombin time, bleeding time and serum calcium have been determined in benzan-throne administered animals at 2, 4, 6, 8, 10, 15 and 30 days. Coagulation time was significantly decreased at 2 days of administration and this decrease remained highly significant upto 10 days. The increase in plasma fibrinogen was highly significant from 2 to 6 days. The number of platelets showed an increase at 2 days which be-came highly significant from 4 to 30 days. Bleeding time was significantly reduced at 10 days. Prothrombin time and serum calcium were unaffected.

Role of the adrenal in hastening blood coagulation after exposure to stress.

The possible role of the adrenal gland in the hastening of blood coagulation in rats exposed to a particular form of stress was investigated. It was observed that there was a marked fall in adrenal cholesterol content during the period of stress. However, the hastening in blood coagulation after exposure to the stress was not altered by removal of the adrenal glands. It, therefore, was concluded that the coagulation phenomenon observed was independent o adrenal activity.