Thrombin blockers have been shown to be effective for various pathological conditions,but their use is limited due to the potential for serious bleeding adverse effects.This study introduced a novel bioactive peptide(...Thrombin blockers have been shown to be effective for various pathological conditions,but their use is limited due to the potential for serious bleeding adverse effects.This study introduced a novel bioactive peptide(P-2-CG) from oyster,that mitigated thrombin-mediated barrier dysfunction and prothrombotic phenotypes in human pulmonary microvascular endothelial cells(HPMECs).P-2-CG significantly attenuated the increase in endothelial monolayer permeability induced by thrombin through the possible attenuation of RhoA activation and it promoted barrier recovery by enhancing endothelial cell adhesion.Additionally,P-2-CG was found to decrease the pro-thrombotic phenotype induced by thrombin in HPMEC by reducing the extrinsic trigger tissue factor mRNA expression,which resulted in prolonged plasma clotting time,decreased Factor Xa activation,and reduced thrombin generation.Moreover,P-2-CG inhibited thrombosis efficiently by blocking intercellular adhesion molecule 1 and vascular cell adhesion protein 1 expression via tyrosine phosphorylation of nuclear factor-κB p65.P-2-CG inhibits thrombin mediated inflammation and provides a potential therapeutic option for treating endothelial dysfunction and thrombosis.展开更多
Aim A capillary zone electrophoretic method （CZE） was used to determine the interactions between natural products and thrombin. Methods Samples containing natural products and thrombin at various ratios were incubat...Aim A capillary zone electrophoretic method （CZE） was used to determine the interactions between natural products and thrombin. Methods Samples containing natural products and thrombin at various ratios were incubated at 25 ℃ and then were separated by CZE with Tris-acetate buffer at pH 7.2. Each run could be accomplished within 5 min. Results In CZE, the peak width broadened due to the affinity interaction between natural products and thrombin. Compared with positive and negative control, the natural products （CB-1, CB-2） from Coreopsis tinctoria Nuttt. interacted with thrombin; CB-3 from Coreopsis tinctoria Nuttt. and HC-1, HC-2, HC-3 from Cistanche deserticola Ma. did not bind to thrombin. Both qualification and quantification characterizations of the binding were determined. Conclusion The established method is capable of sensitive and fast determination of natural products and thrombin interactions, it can be employed as an alternative method.展开更多
To clarify the role of TAFI in hypertensive disorders in pregnancy, 22 subjects, including 10 with pre-eclampsia （PE） and 12 with gestational hypertension were examined for the levels of TAFI and thrombin-antithromb...To clarify the role of TAFI in hypertensive disorders in pregnancy, 22 subjects, including 10 with pre-eclampsia （PE） and 12 with gestational hypertension were examined for the levels of TAFI and thrombin-antithrombin （TAT） complex. Thirty normal pregnant women served as controls. ELISA was employed for the detection. The results showed that the TAFI antigen levels in normal pregnancy group, gestational hypertension group and PE group were （85.35±24.69）%, （99.65±18.27）%, （110.12±23.36）%; （97.06±21.40）%, （114.08±27.76）%, （125.49±24.70）%; （106.6±19.21）%, （129.2±25.07）%, （139.1±30.12）%, in the 1st, 2nd and 3rd trimester respectively. No significant differences were found between the normal pregnancy group and gestational hypertension group but significant difference existed between normal pregnancy group and PE group in each trimester （P〈0.05）. TAT complexes were significantly higher in patients with PE than that in controls （P〈0.05）, but no correlation was found between TAT and TAFI. It is concluded that TAFI may contributed to the impairment of fibrinolysis in the patients with PE and may serves as a sensitive indicator for PE, but it may not help in the diagnosis of the gestational hypertension.展开更多
Objective To evaluate the role of thrombin-activated microglia in the neurodegeneration of nigral dopaminergic neurons in the rat substantia nigra （SN） in vivo. Methods After stereotaxic thrombin injection into unil...Objective To evaluate the role of thrombin-activated microglia in the neurodegeneration of nigral dopaminergic neurons in the rat substantia nigra （SN） in vivo. Methods After stereotaxic thrombin injection into unilateral SN of rats, immunostaining, reverse transcription polymerase chain reaction （RT-PCR） and biochemical methods were used to observe tyrosine hydroxylase （TH） irnmunoreactive positive cells, microglia activation, nitric oxide （NO） amount and inducible nitricoxide synthase （iNOS） expression. Results （1） Selective damage to dopaminergic neurons was produced after thrombin injection, which was evidenced by loss of TH imrnunostaining in time-dependent manner; （2） Strong microglial activation was observed in the SN; （3） RT-PCR demonstrated the early and transient expression of neurotoxic factors iNOS mRNA in the SN. Immunofluorescence results found that thrombin induced expression of iNOS in microglia. The NO production in the thrombininjected rats was significantly higher than that of controls （P 〈 0.05）. Conclusion Thrombin intranigral injection can injure the dopaminergic neurons in the SN. Thrombin-induced microglia activation precedes dopaminergic neuron degeneration, which suggest that activation of microglia and release of NO may play important roles in dopaminergic neuronal death in the SN.展开更多
Sustained accumulatin of 111 indium-labelled platelets is induced in the cerebral vascuiature or rabbits by bolus intracarotid (i. c. ) administration or thrombin (90 U/kg). Bolus i. c. injection of the fibrinolytic, ...Sustained accumulatin of 111 indium-labelled platelets is induced in the cerebral vascuiature or rabbits by bolus intracarotid (i. c. ) administration or thrombin (90 U/kg). Bolus i. c. injection of the fibrinolytic, recombiuant tissue plasminogen activator (rt-PA), 1 miu after thrombin,produced significant inbibition of the. platelet accumulation, albeit substantially less than that produced by 1 min Pretreatment. Hirulogm, PPACK and rt-PA alone had no direct effect on the hasalcirculating levels of 111 In-labedlled platelets in the pulmonary or cranial vasculature at the doses used.Hirulongm and PPACK did not enhance the ability or inrusion or a threshold dose of rt-PA to decrease an established cerebrovascular thromhosis, whereas Defibrotide plus rt-PA produced a significant reduction on accumulated plateiets. These results suggest that fiibrin deposition .plays the impor tant role in the induction and maintenance of the. sustained cerebral platelet accumulation induced bythrombin in this model and Defibrotide can .enhance the pro-fibrinolytic effect of rt-PA although thisProperty is not shared by direct thrombin inhibitors. The sustained platelet accumulation in the cranial vasculature in this model does not appear to be a result or continued generation or endogenousthrombin.展开更多
A rapid, simple, and reproducible method for the preparation of porcine thrombin was investigated. Porcine prothrombin was isolated by carrying out isoelectric precipitation. Porcine thrombin was prepared from prothro...A rapid, simple, and reproducible method for the preparation of porcine thrombin was investigated. Porcine prothrombin was isolated by carrying out isoelectric precipitation. Porcine thrombin was prepared from prothrombin which was activated by the prothrombinase complex containing Factor Xa, Factor V, Ca2+ and phospholipids. Factor Xa and Factor V were isolated by DEAE-cellulose chromatography respectively. They were both identified by SDS-PAGE. Yields and specific activity of porcine thrombin were 107 μg per milliliter plasma and 4 U per milligram protein.展开更多
In order to prepare a novel hemostatic dressing for uncontrolled hemorrhage, a porous chitosan sponge was coated with self-assembled（thrombin/tannic acid）n films, which were based on hydrogen bonding interactions be...In order to prepare a novel hemostatic dressing for uncontrolled hemorrhage, a porous chitosan sponge was coated with self-assembled（thrombin/tannic acid）n films, which were based on hydrogen bonding interactions between thrombin and tannic acid at physiologic p H. According to the whole blood clotting test, the coated chitosan sponges showed a significantly high rate of blood clotting due to the addition of thrombin. On the other hand, the storable half-life of immobilized thrombin is extended to 66.9 days at room temperature, which is 8.5 times longer than unfixed thrombin. It is because of the immobilization effect of, not only the porous structure of chitosan sponge but also the interactions between thrombin and tannic acid. In addition, the tannic acid has similar antibacterial effect to chitosan. Therefore, it is an excellent combination of chitosan, thrombin and tannic acid. Besides, all of materials in this research have been approved by the United States Food and Drug Administration（FDA）. So the chitosan-based sponge is a promising candidate dressing for uncontrolled hemorrhage due to its storable, bio-safe and highly effective hemostatic properties.展开更多
AIM： To examine the role of Fibrinogen-like protein 2 （fgl2）/fibroleukin in tumor development. Fgl2 has been reported to play a vital role in the pathogenesis in MHV-3 （mouse hepatitis virus） induced fulminant an...AIM： To examine the role of Fibrinogen-like protein 2 （fgl2）/fibroleukin in tumor development. Fgl2 has been reported to play a vital role in the pathogenesis in MHV-3 （mouse hepatitis virus） induced fulminant and severe hepatitis, spontaneous abortion, allo- and xenograft rejection by mediating ＂immune coagulation＂.METHODS： Tumor tissues from 133 patients with six types of distinct cancers and the animal tumor tissues from human hepatocellular carcinoma （HCC） model on nude mice （established from high metastasis HCC cell line MHCC97LM6） were obtained. RESULTS： HfgI2 was detected in tumor tissues from 127 out of 133 patients as well as tumor tissues collected from human HCC nude mice. Hfgl2 was highly expressed both in cancer cells and interstitial inflammatory cells including macrophages, NK cells, and CD8^＋ T lymphocytes and vascular endothelial cells. HfgI2 mRNA was localized in cells that expressed hfgI2 protein. Fibrin （nogen） colocalization with hfgl2 expression was determined by dual immunohistochemical staining. In vitro, IL-2 and IFN-γ, increased hfgl2 mRNA by 10-100 folds and protein expression in both THP-1 and HUVEC cell lines. One-stage clotting assays demonstrated that THP-1 and HUVEC cells expressing hfgl2 had increased procoagulant activity following cytokines stimulation. CONCLUSION： The hfgI2 contributes to the hypercoagulability in cancer and may induce tumor angiogenesis and metastasis via cytokine induction.展开更多
The neuro-glial interface extends far beyond mechanical support alone and includes interactions through coagulation cascade proteins. Here, we systematically review the evidence indicating that synaptic and node of Ra...The neuro-glial interface extends far beyond mechanical support alone and includes interactions through coagulation cascade proteins. Here, we systematically review the evidence indicating that synaptic and node of Ranvier glia cell components modulate synaptic transmission and axonal conduction by a coagulation cascade protein system, leading us to propose the concept of the neuro-glial coagulonome. In the peripheral nervous system, the main thrombin receptor protease activated receptor 1 (PAR1) is located on the Schwann microvilli at the node of Ranvier and at the neuromuscular junction. PAR1 activation effects can be both neuroprotective or harmful, depending on thrombin activity levels. Low physiological levels of thrombin induce neuroprotective effects in the Schwann cells which are mediated by the endothelial protein C receptor. High levels of thrombin induce conduction deficits, as found in experimental autoimmune neuritis, the animal model for Guillaine-Barre syndrome. In the central nervous system, PAR1 is located on the peri-synaptic astrocyte end-feet. Its activation by high thrombin levels is involved in the pathology of primary inflammatory brain diseases such as multiple sclerosis, as well as in other central nervous system insults, including trauma, neoplasms, epilepsy and vascular injury. Following activation of PAR1 by high thrombin levels the seizure threshold is lowered. On the other hand, PAR1 activation by lower levels of thrombin in the central nervous system protects against a future ischemic insult. This review presents the known structure and function of the neuro-glial coagulonome, focusing on coagulation, thrombin and PAR1 in a pathway which may be either physiological (neuroprotective) or detrimental in peripheral nervous system and central nervous system diseases. Understanding the neuro-glial coagulonome may open opportunities for novel pharmacological interventions in neurological diseases.展开更多
Post-traumatic hepatic artery pseudoaneurysm is unc-ommon,appearing in approximately 1%of hepatic trauma cases.Most are extrahepatic(80%)and have a late onset.Although they are usually asymptomatic, they should always...Post-traumatic hepatic artery pseudoaneurysm is unc-ommon,appearing in approximately 1%of hepatic trauma cases.Most are extrahepatic(80%)and have a late onset.Although they are usually asymptomatic, they should always be treated becasue of the high risk of complications,especially breakage.Currently the treatment of choice is endovascular embolization with coils or the exclusion of the pseudoaneurysm using other intravascular devices.Recently there have been accounts of a treatment that combines embolization with coils and image-guided percutaneous human thrombin injection.We present a case of post-traumatichepatic artery pseudoaneurysm that was successfully treated using this combined technique.展开更多
AIM:To evaluate the efficacy of human thrombin in the treatment of bleeding gastric and ectopic varices.METHODS:Retrospective observational study in a Tertiary Referral Centre.Between January 1999-October 2005,we iden...AIM:To evaluate the efficacy of human thrombin in the treatment of bleeding gastric and ectopic varices.METHODS:Retrospective observational study in a Tertiary Referral Centre.Between January 1999-October 2005,we identified 37 patients who were endoscopically treated with human thrombin injection therapy for bleeding gastric and ectopic varices.Patient details including age,gender and aetiology of liver disease/segmental portal hypertension were documented.The thrombin was obtained from the Scottish National Blood Transfusion Service and prepared to give a solution of 250 IU/mL which was injected via a standard injection needle.All patient case notes were reviewed and the total dose of thrombin given along with the number of endoscopy sessions was recorded.Initial haemostasis rates,rebleeding rates and mortality were catalogued along with the incidence of any immediate complications which could be attributable to the thrombin therapy.The duration of follow up was also listed.The study was conducted according to the United Kingdom research ethics guidelines.RESULTS:Thirty-seven patients were included.33 patients(89%) had thrombin(250 U/mL) for gastric varices,2(5.4%) for duodenal varices,1 for rectal varices and 1 for gastric and rectal varices.(1) Gastric varices,an average of 15.2 mL of thrombin was used per patient.Re-bleeding occurred in 4 patients(10.8%),managed in 2 by a transjugular intrahepatic portosystemic shunt(TIPSS)(one unsuccessfully who died) and in other 2 by a distal splenorenal shunt;(2) Duodenal varices(or type 2 isolated gastric varices),an average of 12.5 mL was used per patient over 2-3 endoscopy sessions.Re-bleeding occurred in one patient,which was treated by TIPSS;and(3) Rectal varices,an average of 18.3 mL was used per patient over 3 endoscopy sessions.No re-bleeding occurred in this group.CONCLUSION:Human thrombin is a safe,easy to use and effective therapeutic option to control haemorrhage from gastric and ectopic varices.展开更多
Pancreatico-duodenal artery(PDA) pseudoaneurysms are rare vascular conditions with high mortality rates after rupture and they are frequently secondary to pan-creatitis, surgery, trauma or infection. Due to the high r...Pancreatico-duodenal artery(PDA) pseudoaneurysms are rare vascular conditions with high mortality rates after rupture and they are frequently secondary to pan-creatitis, surgery, trauma or infection. Due to the high risk of rupture and bleeding, it is mandatory to treat all pseudoaneurysms, regardless of their size or symp-tomatology. First option of treatment is open surgical repair, but it has high mortality rate, especially in he-modynamically unstable patients. In the recent years, percutaneous ultrasonography(US)- or computed to-mography-guided thrombin injection was proposed as an alternative method for treating visceral aneurysms and pseudoaneurysms, but few reports described this therapy in case of peri-pancreatic pseudoaneurysms. We present a rare case of pseudoaneurysm of the PDA in a patient with no previous history of pancreatitis nor major surgery but with an occlusive lesion of the celiac axis. To the best of our knowledge this is the first reported case of PDA pseudoaneurysm successfully treated in emergency by single transabdominal US-guided injection of thrombin after failed attempts of percutaneous catheterization of the feeding vessel of the pseudoaneurysm.展开更多
In this study,we used plasma factor V activity and parameters of the thrombin generation test to discuss their diagnostic and prognostic value for disseminated intravascular coagulation (DIC) in patients with hematolo...In this study,we used plasma factor V activity and parameters of the thrombin generation test to discuss their diagnostic and prognostic value for disseminated intravascular coagulation (DIC) in patients with hematological malignancies.A total of 164 patients who were diagnosed with hematological malignancies in the Department of Hematology,Union Hospital,between Apr 2014 and Dec.2014 were enrolled in this study.There were 131 patients in the study group and 33 patients in the control group in terms of the laboratory results for DIC.The patients in the study group were divided into a DIC subgroup (n=59) and a non-DIC subgroup (n=72) based on the International Society of Thrombosis and Hemostasis (ISTH) Integral System,and they were divided into four subgroups [score ≤3 (n=35),score=4 (n=37),score=5 (n=47),and score >6 (n=12)] according to ISTH scores.Using 28-day mortality as the endpoint,the patients in the study group were divided into a survival subgroup (n=111) and a non-survival subgroup (n=20).The results showed that the plasma factor V activity was significantly weaker,and lag time and time to peak were significantly shorter in the study group than in the control group (P<0.01).The factor V activity,peak and endogenous thrombin potential (ETP) were significantly decreased in the DIC subgroup as compared with those in the non-DIC subgroup (P<0.01).Among factor V activity,lag time,peak,ETP,and ttPeak,only the factor V activity was significantly decreased in the nonsurvival subgroup compared with the survival subgroup (P<0.01).With the increase in ISTH score,the ETP and peak decreased gradually.The binary logistic regression analysis revealed that PLT,D-dimer,factor V activity and ETP had linear relationship with DIC diagnosed by ISTH Integral System.Using DIC diagnosed by ISTH Integral System as the endpoint,the area under curve (AUC) of factor V activity was found to be similar to that of blood platelet count (PLT) and prothrombin time (PT).In conclusion,factor V activity,ETP and peak had diagnostic value for DIC in patients with hematological malignancies,and only factor V activity had limited prognostic value.展开更多
The aim of this study was to evaluate the efficiency and safety of ultrasound-guided thrombin injection on femoral pseudoaneurysm （FPA） as compared to ultrasound-guided local oppression. Eleven cases of FPA were enr...The aim of this study was to evaluate the efficiency and safety of ultrasound-guided thrombin injection on femoral pseudoaneurysm （FPA） as compared to ultrasound-guided local oppression. Eleven cases of FPA were enrolled and 7 cases received ultrasound-guide thrombin injection （injection group）, and the remaining 4 cases were treated with local oppression （oppression group）. Efficiency and safety were analyzed by ultrasound and subsequent follow-up. The results showed that 1 case relapsed in oppression group while no relapse occurred in thrombin injection group. Ultrasound-guided thrombin injection is better for treatment of FPA in terms of effectiveness and safety.展开更多
Astrocytes are important cellular centers of cholesterol synthesis and metabolism that help maintain normal physiological function at the organism level.Spinal cord injury results in aberrant cholesterol metabolism by...Astrocytes are important cellular centers of cholesterol synthesis and metabolism that help maintain normal physiological function at the organism level.Spinal cord injury results in aberrant cholesterol metabolism by astrocytes and excessive production of oxysterols,which have profound effects on neuropathology.25-Hydroxycholesterol(25-HC),the main product of the membrane-associated enzyme cholesterol-25-hydroxylase(CH25H),plays important roles in mediating neuroinflammation.However,whether the abnormal astrocyte cholesterol metabolism induced by spinal cord injury contributes to the production of 25-HC,as well as the resulting pathological effects,remain unclear.In the present study,spinal cord injury-induced activation of thrombin was found to increase astrocyte CH25H expression.A protease-activated receptor 1 inhibitor was able to attenuate this effect in vitro and in vivo.In cultured primary astrocytes,thrombin interacted with protease-activated receptor 1,mainly through activation of the mitogen-activated protein kinase/nuclear factor-kappa B signaling pathway.Conditioned culture medium from astrocytes in which ch25h expression had been knocked down by siRNA reduced macrophage migration.Finally,injection of the protease activated receptor 1 inhibitor SCH79797 into rat neural sheaths following spinal cord injury reduced migration of microglia/macrophages to the injured site and largely restored motor function.Our results demonstrate a novel regulatory mechanism for thrombin-regulated cholesterol metabolism in astrocytes that could be used to develop anti-inflammatory drugs to treat patients with spinal cord injury.展开更多
To investigate the role of platelet membrane glycoprotein （GP） Ib/Ⅸ/Ⅴ complex and its subunit GP Ibα in patients with hemorrhagic thrombopathy （HT）, the expressions of GP Ib/Ⅸ/Ⅴ complex and GP Ibα,defined as...To investigate the role of platelet membrane glycoprotein （GP） Ib/Ⅸ/Ⅴ complex and its subunit GP Ibα in patients with hemorrhagic thrombopathy （HT）, the expressions of GP Ib/Ⅸ/Ⅴ complex and GP Ibα,defined as mean fluorescence intensity （MFI）, were assessed by flow cytometry. The maximum aggregation of platelet was determined by turbidity method. These indicators were compared among 68 HT patients with the presenting complaint of hemorrhage, 33 well-controlled HT patients and 32 normal healthy subjects. The results showed that the MFI of GP Ib/Ⅸ /Ⅴ complex and GP Ibα was markedly lower in HT patients with current hemorrhage than that in the healthy subjects, with difference being statistically significant （P〈0.05）. There was no significant difference in the expressions of GP Ib/ Ⅸ/ Ⅴ complex and GP Ibα between well-controlled HT patients and normal healthy subjects （P〉0.05）. It was concluded that the expression of GP Ib/Ⅸ /Ⅴ complex, the receptor of thrombin and von Willebrand factor, was down-regulated in HT patients with current hemorrhage, which might result in the dysfunction of platelet aggregation and recurrence of HT.展开更多
Significant progress was achieved in the search of a thrombin receptor antagonist as a novel antithrombotic treatment since the thrombin receptor (protease-activated receptor-1, PAR-1) was cloned 20 years ago. Previou...Significant progress was achieved in the search of a thrombin receptor antagonist as a novel antithrombotic treatment since the thrombin receptor (protease-activated receptor-1, PAR-1) was cloned 20 years ago. Previous works have shown that it is possible to develop potent thrombin receptor antagonists to compete effectively with the receptor’s internal “tethered” ligand to block platelet activation. Vorapaxar (SCH 530348) from Schering-Plough (now Merck) and atopaxar (E5555) from Eisai have been advanced to human clinical trials. Recently, the pivotal phase III clinical trial results for vorapaxar were published. In this article we review these results plus the phase II results from atopaxar. Several newly described thrombin receptor antagonists from the literature will also be discussed. The phase III results from vorapaxar demonstrated that a thrombin receptor antagonist can achieve efficacy in addition to current standard- of-care in treating atherothrombotic patients, especially those with previous myocardial infarction (MI). However, the increased moderate and severe bleeding, especially intracranial bleeding, point to the limitations of current thrombin receptor antagonists. Future thrombin receptor antagonists that can improve on the efficacy and bleeding profile of current ones should have a promising place in meeting the unmet medical need in treating atherothrombotic patients using current standard therapy.展开更多
Objective Calibrated Automated Thrombogram（CAT） is a test to monitor the generation of thrombin. It can be described by four parameters： lag time, peak thrombin, endogenous thrombin potential （ETP） and time to pe...Objective Calibrated Automated Thrombogram（CAT） is a test to monitor the generation of thrombin. It can be described by four parameters： lag time, peak thrombin, endogenous thrombin potential （ETP） and time to peak （ttPeak）. This study aims to determine the normal ranges of CAT parameters in Chinese, and evaluate whether thrombin generation is correlated with the concentration of heparin/Iow molecular weight heparin. Methods Plasma from 120 healthy subjects were collected to determine the normal rangea of CAT parameters in Chinese. Normal plasma pool （NPP, n=25） spiked with different concentrations of heparin or enoxaparin were used to detecte CAT parameters. The overall and age specific normal ranges of CAT parameters were calculated using descriptive statistics method with mean＋-2SD. The correlation between CAT parameters and age or concentrations of heparin, enoxaparin were analyzed with linear regression model. Results The normal ranges for lag time, peak thrombin, ETP, ttPeak in the subjects were 3.648＋2.465 min, 367.39＋151.93 nmol/L, 2277＋_1030 nmol/L.min and 6.372＋_4.280 min respectively. Age was linearly correlated with lag time （r=-0.6583, P〈0.0002）, peak thrombin （r=0.4863, P〈0.0002）, ETP （r=0.3608, P〈0.0014） and ttPeak （r=-0.6323, P〈0.0002）. The values of ETP/peak ratio were linearly correlated with concentrations of heparin. Conclusion The normal ranges of four CAT parameters for Chinese were determined. CAT parameters are associated with age. ETP/peak ratio could be used to monitor the process of anticoagulation therapy.展开更多
Objective： To study the biologic effects of various concentrations of thrombin on aquaporin 4 （AQP4） expression in rat primary cultured astrocytes, and to explore the regulation mechanism of transmembrane water tra...Objective： To study the biologic effects of various concentrations of thrombin on aquaporin 4 （AQP4） expression in rat primary cultured astrocytes, and to explore the regulation mechanism of transmembrane water transportation in astrocytes after intracerebral hemorrhage （ICH）. Methods： Primary cultured astrocytes were incubated in culture mediums containing various concentrations of thrombin for 24 h and harvested. AQP4 mRNA and AQP4 protein expression were determined by reverse transcription polymerase chain reaction （RT-PCR） and immunohistochemical technique. Cell apoptosis was detected by TdT- mediated dUTP nick end labeling （TUNEL） technique. Cell morphology was observed by phase contrast microscope, and cell viability was assayed by MTT. Results： AQP4 mRNA and AQP4 protein showed a low expression in normal astrocytes. The expression of AQP4 mRNA and AQP4 protein significantly increased in the astrocytes treated with 100 U/ml or 200 U/ml thrombin （P 〈 0.01 ）,and these astrocytes swelled. The number of TUNEL positive cells significantly increased. On the other hand, AQP4 mRNA and AQP4 protein expression were downegulated in the astrocytes treated with 0.5 U/ml or 1 U/ml thrombin （P 〈 0.05）, and the cell morphology did not change. Few TUNEL positive cells were observed. Conclusion： AQP4 overxpression induced by high concentrations of thrombin causes an increased permeability of water in astrocytic membrane. On the contrary, the decreased AQP4 expression prevents the astrocytes from swelling and apoptosis.展开更多
基金supported by The National Natural Science Foundation of China (32130085 and 32202021)。
文摘Thrombin blockers have been shown to be effective for various pathological conditions,but their use is limited due to the potential for serious bleeding adverse effects.This study introduced a novel bioactive peptide(P-2-CG) from oyster,that mitigated thrombin-mediated barrier dysfunction and prothrombotic phenotypes in human pulmonary microvascular endothelial cells(HPMECs).P-2-CG significantly attenuated the increase in endothelial monolayer permeability induced by thrombin through the possible attenuation of RhoA activation and it promoted barrier recovery by enhancing endothelial cell adhesion.Additionally,P-2-CG was found to decrease the pro-thrombotic phenotype induced by thrombin in HPMEC by reducing the extrinsic trigger tissue factor mRNA expression,which resulted in prolonged plasma clotting time,decreased Factor Xa activation,and reduced thrombin generation.Moreover,P-2-CG inhibited thrombosis efficiently by blocking intercellular adhesion molecule 1 and vascular cell adhesion protein 1 expression via tyrosine phosphorylation of nuclear factor-κB p65.P-2-CG inhibits thrombin mediated inflammation and provides a potential therapeutic option for treating endothelial dysfunction and thrombosis.
文摘Aim A capillary zone electrophoretic method （CZE） was used to determine the interactions between natural products and thrombin. Methods Samples containing natural products and thrombin at various ratios were incubated at 25 ℃ and then were separated by CZE with Tris-acetate buffer at pH 7.2. Each run could be accomplished within 5 min. Results In CZE, the peak width broadened due to the affinity interaction between natural products and thrombin. Compared with positive and negative control, the natural products （CB-1, CB-2） from Coreopsis tinctoria Nuttt. interacted with thrombin; CB-3 from Coreopsis tinctoria Nuttt. and HC-1, HC-2, HC-3 from Cistanche deserticola Ma. did not bind to thrombin. Both qualification and quantification characterizations of the binding were determined. Conclusion The established method is capable of sensitive and fast determination of natural products and thrombin interactions, it can be employed as an alternative method.
基金a grant from the Key Program of Clinical Sciences of Ministry of Health of China (No. WGCF468)
文摘To clarify the role of TAFI in hypertensive disorders in pregnancy, 22 subjects, including 10 with pre-eclampsia （PE） and 12 with gestational hypertension were examined for the levels of TAFI and thrombin-antithrombin （TAT） complex. Thirty normal pregnant women served as controls. ELISA was employed for the detection. The results showed that the TAFI antigen levels in normal pregnancy group, gestational hypertension group and PE group were （85.35±24.69）%, （99.65±18.27）%, （110.12±23.36）%; （97.06±21.40）%, （114.08±27.76）%, （125.49±24.70）%; （106.6±19.21）%, （129.2±25.07）%, （139.1±30.12）%, in the 1st, 2nd and 3rd trimester respectively. No significant differences were found between the normal pregnancy group and gestational hypertension group but significant difference existed between normal pregnancy group and PE group in each trimester （P〈0.05）. TAT complexes were significantly higher in patients with PE than that in controls （P〈0.05）, but no correlation was found between TAT and TAFI. It is concluded that TAFI may contributed to the impairment of fibrinolysis in the patients with PE and may serves as a sensitive indicator for PE, but it may not help in the diagnosis of the gestational hypertension.
文摘Objective To evaluate the role of thrombin-activated microglia in the neurodegeneration of nigral dopaminergic neurons in the rat substantia nigra （SN） in vivo. Methods After stereotaxic thrombin injection into unilateral SN of rats, immunostaining, reverse transcription polymerase chain reaction （RT-PCR） and biochemical methods were used to observe tyrosine hydroxylase （TH） irnmunoreactive positive cells, microglia activation, nitric oxide （NO） amount and inducible nitricoxide synthase （iNOS） expression. Results （1） Selective damage to dopaminergic neurons was produced after thrombin injection, which was evidenced by loss of TH imrnunostaining in time-dependent manner; （2） Strong microglial activation was observed in the SN; （3） RT-PCR demonstrated the early and transient expression of neurotoxic factors iNOS mRNA in the SN. Immunofluorescence results found that thrombin induced expression of iNOS in microglia. The NO production in the thrombininjected rats was significantly higher than that of controls （P 〈 0.05）. Conclusion Thrombin intranigral injection can injure the dopaminergic neurons in the SN. Thrombin-induced microglia activation precedes dopaminergic neuron degeneration, which suggest that activation of microglia and release of NO may play important roles in dopaminergic neuronal death in the SN.
文摘Sustained accumulatin of 111 indium-labelled platelets is induced in the cerebral vascuiature or rabbits by bolus intracarotid (i. c. ) administration or thrombin (90 U/kg). Bolus i. c. injection of the fibrinolytic, recombiuant tissue plasminogen activator (rt-PA), 1 miu after thrombin,produced significant inbibition of the. platelet accumulation, albeit substantially less than that produced by 1 min Pretreatment. Hirulogm, PPACK and rt-PA alone had no direct effect on the hasalcirculating levels of 111 In-labedlled platelets in the pulmonary or cranial vasculature at the doses used.Hirulongm and PPACK did not enhance the ability or inrusion or a threshold dose of rt-PA to decrease an established cerebrovascular thromhosis, whereas Defibrotide plus rt-PA produced a significant reduction on accumulated plateiets. These results suggest that fiibrin deposition .plays the impor tant role in the induction and maintenance of the. sustained cerebral platelet accumulation induced bythrombin in this model and Defibrotide can .enhance the pro-fibrinolytic effect of rt-PA although thisProperty is not shared by direct thrombin inhibitors. The sustained platelet accumulation in the cranial vasculature in this model does not appear to be a result or continued generation or endogenousthrombin.
文摘A rapid, simple, and reproducible method for the preparation of porcine thrombin was investigated. Porcine prothrombin was isolated by carrying out isoelectric precipitation. Porcine thrombin was prepared from prothrombin which was activated by the prothrombinase complex containing Factor Xa, Factor V, Ca2+ and phospholipids. Factor Xa and Factor V were isolated by DEAE-cellulose chromatography respectively. They were both identified by SDS-PAGE. Yields and specific activity of porcine thrombin were 107 μg per milliliter plasma and 4 U per milligram protein.
基金financially supported by the National Natural Science Foundation of China(Nos.21104067,21274127 and 21374099 and 51473144)Key Basic Research Development Plan(973 Program)of China(Nos.2009CB930104 and 2011CB606203)+1 种基金Fundamental Research Funds for the Central Universities(No.2013QNA4048)Technology Foundation for Selected Overseas Scholar of Zhejiang Province
文摘In order to prepare a novel hemostatic dressing for uncontrolled hemorrhage, a porous chitosan sponge was coated with self-assembled（thrombin/tannic acid）n films, which were based on hydrogen bonding interactions between thrombin and tannic acid at physiologic p H. According to the whole blood clotting test, the coated chitosan sponges showed a significantly high rate of blood clotting due to the addition of thrombin. On the other hand, the storable half-life of immobilized thrombin is extended to 66.9 days at room temperature, which is 8.5 times longer than unfixed thrombin. It is because of the immobilization effect of, not only the porous structure of chitosan sponge but also the interactions between thrombin and tannic acid. In addition, the tannic acid has similar antibacterial effect to chitosan. Therefore, it is an excellent combination of chitosan, thrombin and tannic acid. Besides, all of materials in this research have been approved by the United States Food and Drug Administration（FDA）. So the chitosan-based sponge is a promising candidate dressing for uncontrolled hemorrhage due to its storable, bio-safe and highly effective hemostatic properties.
基金The Natural Science Foundation of China,NSFC (30672380,30571643)National Key Basic Research Program of China (2007CB512900,2005CB522901,2005CB522507)11th Five-Year Plan Key Project (2006BAI05A07)
文摘AIM： To examine the role of Fibrinogen-like protein 2 （fgl2）/fibroleukin in tumor development. Fgl2 has been reported to play a vital role in the pathogenesis in MHV-3 （mouse hepatitis virus） induced fulminant and severe hepatitis, spontaneous abortion, allo- and xenograft rejection by mediating ＂immune coagulation＂.METHODS： Tumor tissues from 133 patients with six types of distinct cancers and the animal tumor tissues from human hepatocellular carcinoma （HCC） model on nude mice （established from high metastasis HCC cell line MHCC97LM6） were obtained. RESULTS： HfgI2 was detected in tumor tissues from 127 out of 133 patients as well as tumor tissues collected from human HCC nude mice. Hfgl2 was highly expressed both in cancer cells and interstitial inflammatory cells including macrophages, NK cells, and CD8^＋ T lymphocytes and vascular endothelial cells. HfgI2 mRNA was localized in cells that expressed hfgI2 protein. Fibrin （nogen） colocalization with hfgl2 expression was determined by dual immunohistochemical staining. In vitro, IL-2 and IFN-γ, increased hfgl2 mRNA by 10-100 folds and protein expression in both THP-1 and HUVEC cell lines. One-stage clotting assays demonstrated that THP-1 and HUVEC cells expressing hfgl2 had increased procoagulant activity following cytokines stimulation. CONCLUSION： The hfgI2 contributes to the hypercoagulability in cancer and may induce tumor angiogenesis and metastasis via cytokine induction.
文摘The neuro-glial interface extends far beyond mechanical support alone and includes interactions through coagulation cascade proteins. Here, we systematically review the evidence indicating that synaptic and node of Ranvier glia cell components modulate synaptic transmission and axonal conduction by a coagulation cascade protein system, leading us to propose the concept of the neuro-glial coagulonome. In the peripheral nervous system, the main thrombin receptor protease activated receptor 1 (PAR1) is located on the Schwann microvilli at the node of Ranvier and at the neuromuscular junction. PAR1 activation effects can be both neuroprotective or harmful, depending on thrombin activity levels. Low physiological levels of thrombin induce neuroprotective effects in the Schwann cells which are mediated by the endothelial protein C receptor. High levels of thrombin induce conduction deficits, as found in experimental autoimmune neuritis, the animal model for Guillaine-Barre syndrome. In the central nervous system, PAR1 is located on the peri-synaptic astrocyte end-feet. Its activation by high thrombin levels is involved in the pathology of primary inflammatory brain diseases such as multiple sclerosis, as well as in other central nervous system insults, including trauma, neoplasms, epilepsy and vascular injury. Following activation of PAR1 by high thrombin levels the seizure threshold is lowered. On the other hand, PAR1 activation by lower levels of thrombin in the central nervous system protects against a future ischemic insult. This review presents the known structure and function of the neuro-glial coagulonome, focusing on coagulation, thrombin and PAR1 in a pathway which may be either physiological (neuroprotective) or detrimental in peripheral nervous system and central nervous system diseases. Understanding the neuro-glial coagulonome may open opportunities for novel pharmacological interventions in neurological diseases.
基金Supported by Departments of Radiology and Surgery at University general hospital Virgen de la Arrixaca
文摘Post-traumatic hepatic artery pseudoaneurysm is unc-ommon,appearing in approximately 1%of hepatic trauma cases.Most are extrahepatic(80%)and have a late onset.Although they are usually asymptomatic, they should always be treated becasue of the high risk of complications,especially breakage.Currently the treatment of choice is endovascular embolization with coils or the exclusion of the pseudoaneurysm using other intravascular devices.Recently there have been accounts of a treatment that combines embolization with coils and image-guided percutaneous human thrombin injection.We present a case of post-traumatichepatic artery pseudoaneurysm that was successfully treated using this combined technique.
文摘AIM:To evaluate the efficacy of human thrombin in the treatment of bleeding gastric and ectopic varices.METHODS:Retrospective observational study in a Tertiary Referral Centre.Between January 1999-October 2005,we identified 37 patients who were endoscopically treated with human thrombin injection therapy for bleeding gastric and ectopic varices.Patient details including age,gender and aetiology of liver disease/segmental portal hypertension were documented.The thrombin was obtained from the Scottish National Blood Transfusion Service and prepared to give a solution of 250 IU/mL which was injected via a standard injection needle.All patient case notes were reviewed and the total dose of thrombin given along with the number of endoscopy sessions was recorded.Initial haemostasis rates,rebleeding rates and mortality were catalogued along with the incidence of any immediate complications which could be attributable to the thrombin therapy.The duration of follow up was also listed.The study was conducted according to the United Kingdom research ethics guidelines.RESULTS:Thirty-seven patients were included.33 patients(89%) had thrombin(250 U/mL) for gastric varices,2(5.4%) for duodenal varices,1 for rectal varices and 1 for gastric and rectal varices.(1) Gastric varices,an average of 15.2 mL of thrombin was used per patient.Re-bleeding occurred in 4 patients(10.8%),managed in 2 by a transjugular intrahepatic portosystemic shunt(TIPSS)(one unsuccessfully who died) and in other 2 by a distal splenorenal shunt;(2) Duodenal varices(or type 2 isolated gastric varices),an average of 12.5 mL was used per patient over 2-3 endoscopy sessions.Re-bleeding occurred in one patient,which was treated by TIPSS;and(3) Rectal varices,an average of 18.3 mL was used per patient over 3 endoscopy sessions.No re-bleeding occurred in this group.CONCLUSION:Human thrombin is a safe,easy to use and effective therapeutic option to control haemorrhage from gastric and ectopic varices.
文摘Pancreatico-duodenal artery(PDA) pseudoaneurysms are rare vascular conditions with high mortality rates after rupture and they are frequently secondary to pan-creatitis, surgery, trauma or infection. Due to the high risk of rupture and bleeding, it is mandatory to treat all pseudoaneurysms, regardless of their size or symp-tomatology. First option of treatment is open surgical repair, but it has high mortality rate, especially in he-modynamically unstable patients. In the recent years, percutaneous ultrasonography(US)- or computed to-mography-guided thrombin injection was proposed as an alternative method for treating visceral aneurysms and pseudoaneurysms, but few reports described this therapy in case of peri-pancreatic pseudoaneurysms. We present a rare case of pseudoaneurysm of the PDA in a patient with no previous history of pancreatitis nor major surgery but with an occlusive lesion of the celiac axis. To the best of our knowledge this is the first reported case of PDA pseudoaneurysm successfully treated in emergency by single transabdominal US-guided injection of thrombin after failed attempts of percutaneous catheterization of the feeding vessel of the pseudoaneurysm.
文摘In this study,we used plasma factor V activity and parameters of the thrombin generation test to discuss their diagnostic and prognostic value for disseminated intravascular coagulation (DIC) in patients with hematological malignancies.A total of 164 patients who were diagnosed with hematological malignancies in the Department of Hematology,Union Hospital,between Apr 2014 and Dec.2014 were enrolled in this study.There were 131 patients in the study group and 33 patients in the control group in terms of the laboratory results for DIC.The patients in the study group were divided into a DIC subgroup (n=59) and a non-DIC subgroup (n=72) based on the International Society of Thrombosis and Hemostasis (ISTH) Integral System,and they were divided into four subgroups [score ≤3 (n=35),score=4 (n=37),score=5 (n=47),and score >6 (n=12)] according to ISTH scores.Using 28-day mortality as the endpoint,the patients in the study group were divided into a survival subgroup (n=111) and a non-survival subgroup (n=20).The results showed that the plasma factor V activity was significantly weaker,and lag time and time to peak were significantly shorter in the study group than in the control group (P<0.01).The factor V activity,peak and endogenous thrombin potential (ETP) were significantly decreased in the DIC subgroup as compared with those in the non-DIC subgroup (P<0.01).Among factor V activity,lag time,peak,ETP,and ttPeak,only the factor V activity was significantly decreased in the nonsurvival subgroup compared with the survival subgroup (P<0.01).With the increase in ISTH score,the ETP and peak decreased gradually.The binary logistic regression analysis revealed that PLT,D-dimer,factor V activity and ETP had linear relationship with DIC diagnosed by ISTH Integral System.Using DIC diagnosed by ISTH Integral System as the endpoint,the area under curve (AUC) of factor V activity was found to be similar to that of blood platelet count (PLT) and prothrombin time (PT).In conclusion,factor V activity,ETP and peak had diagnostic value for DIC in patients with hematological malignancies,and only factor V activity had limited prognostic value.
文摘The aim of this study was to evaluate the efficiency and safety of ultrasound-guided thrombin injection on femoral pseudoaneurysm （FPA） as compared to ultrasound-guided local oppression. Eleven cases of FPA were enrolled and 7 cases received ultrasound-guide thrombin injection （injection group）, and the remaining 4 cases were treated with local oppression （oppression group）. Efficiency and safety were analyzed by ultrasound and subsequent follow-up. The results showed that 1 case relapsed in oppression group while no relapse occurred in thrombin injection group. Ultrasound-guided thrombin injection is better for treatment of FPA in terms of effectiveness and safety.
基金supported by the National Natural Science Foundation of ChinaNo.81971826 (to AG)+5 种基金the China Postdoctoral Science FoundationNo.2020M681 689 (to YH)the Scientific Research Project of The Health Commission of Jiangsu ProvinceNo.ZDB2020003 (to AG)the Basic Scientific Research Projects of NantongNo.JC2020041 (to YH)
文摘Astrocytes are important cellular centers of cholesterol synthesis and metabolism that help maintain normal physiological function at the organism level.Spinal cord injury results in aberrant cholesterol metabolism by astrocytes and excessive production of oxysterols,which have profound effects on neuropathology.25-Hydroxycholesterol(25-HC),the main product of the membrane-associated enzyme cholesterol-25-hydroxylase(CH25H),plays important roles in mediating neuroinflammation.However,whether the abnormal astrocyte cholesterol metabolism induced by spinal cord injury contributes to the production of 25-HC,as well as the resulting pathological effects,remain unclear.In the present study,spinal cord injury-induced activation of thrombin was found to increase astrocyte CH25H expression.A protease-activated receptor 1 inhibitor was able to attenuate this effect in vitro and in vivo.In cultured primary astrocytes,thrombin interacted with protease-activated receptor 1,mainly through activation of the mitogen-activated protein kinase/nuclear factor-kappa B signaling pathway.Conditioned culture medium from astrocytes in which ch25h expression had been knocked down by siRNA reduced macrophage migration.Finally,injection of the protease activated receptor 1 inhibitor SCH79797 into rat neural sheaths following spinal cord injury reduced migration of microglia/macrophages to the injured site and largely restored motor function.Our results demonstrate a novel regulatory mechanism for thrombin-regulated cholesterol metabolism in astrocytes that could be used to develop anti-inflammatory drugs to treat patients with spinal cord injury.
基金supported by a grant from the National Natural Science Foundation of China (No. 30572441).
文摘To investigate the role of platelet membrane glycoprotein （GP） Ib/Ⅸ/Ⅴ complex and its subunit GP Ibα in patients with hemorrhagic thrombopathy （HT）, the expressions of GP Ib/Ⅸ/Ⅴ complex and GP Ibα,defined as mean fluorescence intensity （MFI）, were assessed by flow cytometry. The maximum aggregation of platelet was determined by turbidity method. These indicators were compared among 68 HT patients with the presenting complaint of hemorrhage, 33 well-controlled HT patients and 32 normal healthy subjects. The results showed that the MFI of GP Ib/Ⅸ /Ⅴ complex and GP Ibα was markedly lower in HT patients with current hemorrhage than that in the healthy subjects, with difference being statistically significant （P〈0.05）. There was no significant difference in the expressions of GP Ib/ Ⅸ/ Ⅴ complex and GP Ibα between well-controlled HT patients and normal healthy subjects （P〉0.05）. It was concluded that the expression of GP Ib/Ⅸ /Ⅴ complex, the receptor of thrombin and von Willebrand factor, was down-regulated in HT patients with current hemorrhage, which might result in the dysfunction of platelet aggregation and recurrence of HT.
文摘Significant progress was achieved in the search of a thrombin receptor antagonist as a novel antithrombotic treatment since the thrombin receptor (protease-activated receptor-1, PAR-1) was cloned 20 years ago. Previous works have shown that it is possible to develop potent thrombin receptor antagonists to compete effectively with the receptor’s internal “tethered” ligand to block platelet activation. Vorapaxar (SCH 530348) from Schering-Plough (now Merck) and atopaxar (E5555) from Eisai have been advanced to human clinical trials. Recently, the pivotal phase III clinical trial results for vorapaxar were published. In this article we review these results plus the phase II results from atopaxar. Several newly described thrombin receptor antagonists from the literature will also be discussed. The phase III results from vorapaxar demonstrated that a thrombin receptor antagonist can achieve efficacy in addition to current standard- of-care in treating atherothrombotic patients, especially those with previous myocardial infarction (MI). However, the increased moderate and severe bleeding, especially intracranial bleeding, point to the limitations of current thrombin receptor antagonists. Future thrombin receptor antagonists that can improve on the efficacy and bleeding profile of current ones should have a promising place in meeting the unmet medical need in treating atherothrombotic patients using current standard therapy.
基金supported by grant from the Ministry of Education of China(grant No.20110001120088)
文摘Objective Calibrated Automated Thrombogram（CAT） is a test to monitor the generation of thrombin. It can be described by four parameters： lag time, peak thrombin, endogenous thrombin potential （ETP） and time to peak （ttPeak）. This study aims to determine the normal ranges of CAT parameters in Chinese, and evaluate whether thrombin generation is correlated with the concentration of heparin/Iow molecular weight heparin. Methods Plasma from 120 healthy subjects were collected to determine the normal rangea of CAT parameters in Chinese. Normal plasma pool （NPP, n=25） spiked with different concentrations of heparin or enoxaparin were used to detecte CAT parameters. The overall and age specific normal ranges of CAT parameters were calculated using descriptive statistics method with mean＋-2SD. The correlation between CAT parameters and age or concentrations of heparin, enoxaparin were analyzed with linear regression model. Results The normal ranges for lag time, peak thrombin, ETP, ttPeak in the subjects were 3.648＋2.465 min, 367.39＋151.93 nmol/L, 2277＋_1030 nmol/L.min and 6.372＋_4.280 min respectively. Age was linearly correlated with lag time （r=-0.6583, P〈0.0002）, peak thrombin （r=0.4863, P〈0.0002）, ETP （r=0.3608, P〈0.0014） and ttPeak （r=-0.6323, P〈0.0002）. The values of ETP/peak ratio were linearly correlated with concentrations of heparin. Conclusion The normal ranges of four CAT parameters for Chinese were determined. CAT parameters are associated with age. ETP/peak ratio could be used to monitor the process of anticoagulation therapy.
文摘Objective： To study the biologic effects of various concentrations of thrombin on aquaporin 4 （AQP4） expression in rat primary cultured astrocytes, and to explore the regulation mechanism of transmembrane water transportation in astrocytes after intracerebral hemorrhage （ICH）. Methods： Primary cultured astrocytes were incubated in culture mediums containing various concentrations of thrombin for 24 h and harvested. AQP4 mRNA and AQP4 protein expression were determined by reverse transcription polymerase chain reaction （RT-PCR） and immunohistochemical technique. Cell apoptosis was detected by TdT- mediated dUTP nick end labeling （TUNEL） technique. Cell morphology was observed by phase contrast microscope, and cell viability was assayed by MTT. Results： AQP4 mRNA and AQP4 protein showed a low expression in normal astrocytes. The expression of AQP4 mRNA and AQP4 protein significantly increased in the astrocytes treated with 100 U/ml or 200 U/ml thrombin （P 〈 0.01 ）,and these astrocytes swelled. The number of TUNEL positive cells significantly increased. On the other hand, AQP4 mRNA and AQP4 protein expression were downegulated in the astrocytes treated with 0.5 U/ml or 1 U/ml thrombin （P 〈 0.05）, and the cell morphology did not change. Few TUNEL positive cells were observed. Conclusion： AQP4 overxpression induced by high concentrations of thrombin causes an increased permeability of water in astrocytic membrane. On the contrary, the decreased AQP4 expression prevents the astrocytes from swelling and apoptosis.
