慢性肾脏疾病血清和尿液纤溶活性物质的改变及临床意义

目的探讨慢性肾脏疾病血清和尿液纤溶活性物质的改变及其临床意义。方法选择38例慢性肾小球肾炎(CGN),28例肾病综合征(NS),36例非透析治疗的慢性肾功能不全(CRF)和20例正常对照作为研究对象,应用ELISA法检测血清和尿液中组织型纤溶酶原激活剂(t-PA)和纤溶酶原激活物抑制剂-1(PAI-1)的浓度,同时分析尿中t-PA和PAI-1的水平与血t-PA、PAI-1、血肌酐和24h尿蛋白总量之间相关性。结果慢性肾脏疾病出现血清t-PA、PAI-1升高,尿液t-PA、PAI-1降低,其中尿液t-PA、PAI-1的改变独立于血清,不受血肌酐和24h尿蛋白定量的影响。结论慢性肾脏疾病患者存在纤溶活性物质的异常,其中尿液纤溶活性物质的改变可反应肾脏内皮细胞损伤。     

登革2型病毒调控血管内皮细胞纤溶系统相关蛋白的表达

目的观察登革2型病毒（DV2）对人脐静脉血管内皮细胞（HUVEC）表达组织纤溶酶原激活物（tPA）和纤溶酶原激活物抑制物1（PAI-1）的影响。方法应用胰酶消化分离HUVEC并进行传代培养，用生长良好的第2．3代细胞进行试验。用cell counting kit-8（CCK-8）测定DV2感染后细胞活性变化；发色底物法测定感染DV2组和对照组培养液中tPA、PAI-1活性；RT-PCR检测细胞内tPA和PAI-1 mRNA水平。结果DV2感染对细胞活力的影响与对照组相比差异无统计学意义。感染DV2组培养液中tPA活性在12～72h显著升高（P〈0．05）；DV2诱导HUVEC表达tPA mRNA的水平显著上调，12h达到峰值，以后渐降，72h mRNA表达水平仍高于对照组（P〈0．01）。而DV2感染组培养液中PAI-1活性和PAI-1 mRNA的表达与对照组比较差异无统计学意义（P〉0．05）。结论DV2感染可显著上调HUVEC的tPA mRNA转录，增强内皮细胞tPA蛋白的分泌，而不影响PAI-1 mRNA的转录或改变内皮细胞PAI-1的分泌。结果提示DV2可活化但并不损伤内皮细胞，诱发内皮细胞增强表达纤溶酶原激活物而致使纤溶系统失衡，引起纤溶亢进，这可能是诱发DHF／DSS患者急性期出血、低血容量性休克等体征的主要因素之一。     

尼古丁对血管内皮细胞释放t-PA及PAI-1的影响

目的: 研究尼古丁对人脐静脉内皮细胞(HUVECs)释放组织型纤溶酶原激活物(t-PA)和纤溶酶原激活物抑制物-1(PAI-1)的影响。方法: HUVECs培养后接种于24孔培养板中,随机分为对照组及实验组,分别进行以下实验。(1)以0.1、1、10、100 μmol/L 尼古丁孵育HUVECs,12 h后收集各组上清液;(2)以100 μmol/L尼古丁与HUVECs孵育0、4、6、8、12 及24 h,收集各组上清液。采用ELISA法测定各组t-PA和PAI-1的浓度。结果: HUVECs与不同浓度尼古丁孵育12 h后,100 μmol/L尼古丁组PAI-1蛋白较对照组明显增加(P<0.01);0.1、1及10 μmol/L尼古丁组PAI-1蛋白与对照组比较,均无显著差异(均P>0.05);各浓度组t-PA蛋白与对照组比较,均无显著差异(均P>0.05)。HUVECs 与100 μmol/L的尼古丁分别孵育4 、6 、8 、12 及24 h,各组PAI-1蛋白均较对照组明显升高(P<0.05),且其升高呈时间依赖性;各组t-PA与对照组比较,均无显著差异(均P>0.05)。结论: 尼古丁可抑制HUVECs的纤溶活性,对内皮细胞具有损伤作用。     

蝎蜂毒肽对大鼠纤溶系统作用初探

本研究采用大鼠肢体血管灌流和整体给药两种模型，观察蝎蜂毒（ＳＢＰ）对血管理灌流液内纤溶酶原激活物（ＰＡ）活性、血浆优球蛋白纤溶性（ＥＦＡ）和纤溶酶（ＰＬ）活性的影响。结果说明，ＳＢＰ有明显激活纤溶系统作用；其机制可能涉及血管内皮细胞释放ＰＡ活性增加，进一步促使纤溶酶原活化为ＰＬ增多的途径。     

代谢综合征患者纤溶活性与胰岛素抵抗的关系

目的:探讨代谢综合征患者血浆纤溶活性及与胰岛素抵抗的关系。方法:选择单纯代谢综合征患者36例,代谢综合征合并冠心病患者44例和健康人群对照20例。观察一般情况,并测定血浆纤溶酶原激活抑制物-1(PAI-1)和组织型纤溶酶原激活物(t-PA)、纤维蛋白原(Fib)、空腹血糖(FBG)、空腹血胰岛素(Ins)和血脂等指标;计算胰岛素敏感指数(ISI)。结果:代谢综合征患者的ISI较正常对照组明显下降(P<0.05);血浆PAI-1、Fib等明显升高(P<0.05)。代谢综合征合并冠心病组PAI-1与Fib、Ins正相关,与ISI、高密度脂蛋白(HDL)负相关。结论:代谢综合征患者存在明显的胰岛素抵抗和纤溶活性异常,同时纤溶活性异常与胰岛素抵抗相关。     

妊娠高血压综合征患者vWF、t-PA、PAI-1的检测分析

目的:探讨妊娠高血压综合征(妊高征)患者内皮细胞功能指标的变化及其临床意义。方法:应用ELISA法及发色底物法测定妊高征患者血浆血管性血友病因子(vWF)、织织型纤溶酶原激活物(t-PA)及纤溶酶原激活抑制物-1(PAI-1)活性。结果:妊高征患者vWF、t-PA、PAI-1较正常非孕组明显升高(P<0.05或P<0.01);妊高征各组患者vWF、PAI-1活性比正常晚孕组显著增高(P<0.05或P<0.01),且病情越重增高越明显;t-PA无明显改变。中、重度妊高征组血浆vWF与PAI-1水平呈直线正相关关系(r=0.723,P<0.05;r=0.765,P<0.05)。结论:妊高征患者内皮细胞功能异常,凝血及纤溶抑制功能亢进。测定血浆vWF和PAI-1水平,对于临床诊断妊高征有重要意义。     

ACI患者血浆ET-1和t—PA、PAI-1水平的相关性分析

内皮素（Endothelin－1,ET－1）为体内最强的缩血管多肽。纤溶系统在急性脑梗死（ACI）的发生发展中起着十分重要的作用,组织型纤溶酶原激活物（t-PA）和纤溶酶原激活物抑制物-1（PAI-1）的水平是纤溶活性的重要检测指标,     

蚯蚓蛋白激酶对体内纤溶活性的增强作用研究

目的：探讨蚯蚓蛋白激酶制剂（LK）的纤溶增强作用。方法：采用静脉给药方法，观察LK对SD大鼠纤溶激活因子t-PA及其抑制物PAI-1的急性作用。结果：给药后，PAI-1活性被显著抑制（P<0.01），t-PA活性则明显增强（P<0.01）。剂量1200 U/kg体重的LK，其增强t-PA作用显著大于600U/kg体重剂量LK（P<0.05）。此外，体外观察表明:LK具有明显的激活纤溶酶原（Plg）作用，且有量-效关系，具有一定的浓度依赖性（1.56-25 kU/L）。结论：结果表明，LK具备增强纤溶的特性，静脉给药作用快速而肯定。     

凝血、纤溶状态与糖尿病肾病

目的观察2型糖尿病（Diabetes mellitus，DM）患者的凝血、纤溶状态指标在糖尿病肾病（Diabetic nephropathy，DN）各期的水平，探讨其在DN发生、发展中的作用。方法检测30例正常人和90例2型DM患者凝血、纤溶状态指标：抗凝血酶-Ⅲ（AT-Ⅲ）、凝血酶-抗凝血酶复合物（TAT），组织型纤溶酶原激活剂（t-PA），纤溶酶原激活抑制物-1（PAI-1）。结果①DM各组血浆TAT水平高于正常对照组，t-PA水平、AT活性低于正常对照组，在DM无并发症时即出现上述改变（P〈0．01）。②血浆PAI-1水平在DN正常白蛋白尿组出现有统计学意义的升高（P分别〈0．05）。结论①DM在无并发症时，即存在凝血活性亢进、纤溶系统活性抑制。②PAJ-1是早期诊断DN较敏感的指标，并能反映DN的发生和发展，与尿白蛋白排泄量（Urinary Albumin Excretion，UAE）指标联合检测有助于早期诊断DN。     

妊娠糖尿病孕妇糖化血红蛋白与部分止凝血指标活性的相关性

目的探讨妊娠糖尿病（GDM）孕妇的部分凝血、纤溶指标活性的变化及其与糖化血红蛋白（GHbA1c）的相关性。方法对正常非孕妇女、正常妊娠妇女（各40例）和GDM孕妇（50例）的GHbA1c、血浆Ⅶc因子（FⅦc）、组织型纤溶酶原激活物（t-PA）及其抑制物（PAI-1）、蛋白C活性依赖凝固时间（PCAT）及抗凝血酶-Ⅲ（AT-Ⅲ）等指标进行检测,并分析糖化血红蛋白与各指标之间的相关性。结果与正常非孕组及正常妊娠组比较,GDM组GHbA1c、FⅦc、PAI-1均显著增高（P〈0．01）,t-PA明显下降（P〈0．01）;正常妊娠组AT-Ⅲ较非孕组呈下降趋势,GDM患者AT-Ⅲ水平、PCAT与正常妊娠组无显著差异。全部GDM患者GHbA1c与t-PA呈负相关（r=-0．607．P〈0．01）,与PAI-1呈正相关（r=0．493,P〈0．01）,与FⅦc活性正相关（r=0．421,P〈0．01）。结论糖尿病孕妇存在着明显的血栓前状态,血糖通过影响纤溶凝血系统功能,导致凝血功能异常,在妊娠糖尿病的发生发展中起着重要的作用。提示应密切关注患者糖化血红蛋白及凝血纤溶指标的变化,预防并发症的发生。     

冠状动脉介入治疗患者tPA、D-二聚体、FDP检测的临床应用

目的:动态观察冠心病患者冠状动脉介入(PCI)治疗前后血浆组织纤溶酶原激活物(tPA)、D-二聚体(D-D)、纤维蛋白(原)降解产物(FDP)含量。方法:用ELISA对60例冠心病患者PCI术前、术后即刻和术后5天以及40例非手术对照组上述指标进行检测和比较;并进行门诊随访分析。结果:冠心病患者术前tPA含量明显低于对照组(P<0.05),D-D、FDP含量明显高于对照组(P<0.05);PCI术后即刻tPA较术前明显降低(P<0.01),术后5天回升至术前水平,但仍比对照组明显降低(P<0.01);D-D、FDP含量术后即刻较术前明显升高(P<0.01),术后5天下降至与术前无明显差异,但仍高于对照组(P<0.01)。门诊随访31例PCI术后疗效稳定患者tPA、D-D、FDP均与对照组无显著性差异(P>0.05)。结论:PCI可能造成冠心病患者血管内膜损伤而导致机体纤溶功能短期降低。     

Effects of a long-term pharmacological interruption of the renin-angiotensin system on the fibrinolytic system in essential hypertension

To assess the effects of pharmacological interruption of the renin-angiotensin system on the fibrinolysis, tissue plasminogen activator antigen (t-PA), plasminogen activator inhibitor-1 antigens (PAI-1) and neurohormones, such as plasma renin activity, norepinephrine, angiotensin II (AII) and IV (AIV) concentrations, were measured in 60 hypertensives. Among them, 48 patients were divided into two groups (25 with 10-20 mg quinapril and 23 with 50-100 mg losartan) who received the drug for 6 months. AII had a weak positive correlation with free PAI-I (n = 60, r = 0.26, p < 0.05) whereas AIV had a strong positive correlation with free PAI-I (n = 60, r = 0.57, p < 0.0001). In both treatment groups, blood pressures were significantly reduced to similar levels after drug treatment. While plasma renin activity increased significantly in both groups after drug treatment, only the losartan group showed significant increases in AII and AIV concentrations. In the quinapril group, there was a significant change in t-PA (p < 0.001) without changes in PAI-1. In the losartan group, free PAI-I and total PAI-I (p < 0.05 for free PAI-I and p < 0.04 for total PAI-I) were significantly increased without a change in t-PA. Thus, quinapril enhanced fibrinolysis but losartan attenuated it. These unique effects of each drug on the fibrinolytic system appear to be associated with changes in AII and AIV concentrations.     

Untersuchung zur Frage von persistierenden Veränderungen der Fibrinolyseparameter t-PA und PAI bei Patienten nach juvenilem ischämischen cerebralem Insult

Summary In diseases associated with thrombotic or thromboembolic complications, a reduction in the fibrinolytic potential may contribute to the risk to develop thrombosis.To investigate whether iuvenile cerebral infarction is associated with a permanent defect of the fibrinolytic system we measured the main components of the fibrinolytic system, tissue plasminogen activator (t-PA) and its fast acting inhibitor (PAI) in plasma samples of 21 patients (aged 21–44 years) 3–24 months after the acute event. The data obtained were compared to those from thirteen healthy young volunteers (22–46 years). A direct effect of known risk factors on the fibrinolytic system could be excluded because patients avoided their risk factors immediately after the ischemic cerebral attack. Hypertension and the combination of oral contraceptives and smoking had been the most striking original risk factors.Levels of t-PA antigen and t-PA activity before and after venous occlusion, or PAI activity were not different between patients and controls suggesting that at least a permanent decrease in the activity of the fibrinolytic system does not exist in these patients. However, our findings do not exclude that a temporary defect in fibrinolysis might have contributed to the acute onset of the thrombotic cerebral event possibly induced by the risk factors originally present.

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Abkürzungen t-PA tissue plasminogen activator - PAI plasminogen activator inhibitor - RIND reversibles ischämisches neurologisches Defizit - KS kompletter Schlaganfall - TIA transitorisch ischämische Attacke     

Increased plasma levels of a rapid inhibitor of tissue plasminogen activator in young survivors of myocardial infarction

Certain risk factors for myocardial infarction have been linked with disturbances in fibrinolytic activity. The recent development in our laboratory of new sensitive and specific methods for determination of tissue plasminogen activator (t-PA) activity and antigen, as well as the discovery of a new rapid inhibitor of this enzyme, enabled us to study fibrinolytic function in detail in a representative population of postinfarction patients. Seventy-one patients (62 men and 9 women) who had survived a myocardial infarction before the age of 45 were compared with 50 healthy subjects of similar age, three years after the infarction. Low t-PA activity after venous occlusion, mostly explained by high plasma levels of the t-PA inhibitor and to some extent by impaired release of t-PA from the vessel wall, was a frequent finding in the patients. The level of t-PA inhibitor was positively and significantly correlated with levels of serum triglycerides. Our data suggest that reduced fibrinolytic capacity due to increased plasma levels of a rapid inhibitor of t-PA may have pathogenetic importance in myocardial infarction, particularly in patients with hypertriglyceridemia.     

Tissue plasminogen activator, plasminogen activator inhibitors, and activator-inhibitor complex in liver disease.

AIMS--To identify the relative contribution of plasminogen activators, particularly tissue plasminogen activator (t-PA) and specific plasminogen activator inhibitors (PAI-1, PAI-2), to the fibrinolytic changes associated with various types of liver disease or severe chemical and physical damage to the liver. METHODS--Platelet rich (PRP) and platelet poor plasma (PFP) from patients with alcoholic cirrhosis, primary biliary cirrhosis, hepatic malignancy, or paracetamol overdose, or who were undergoing partial hepatectomy or liver transplantation, were assayed for t-PA, PAI-1, t-PA-PAI-1 complex and PAI-2 antigen values using specific enzyme linked immunosorbent assays (ELISAs) developed in this laboratory. RESULTS--Appreciable increases in the plasma concentration of t-PA, PAI-1, and t-PA-PAI-1 were seen in patients with alcoholic cirrhosis, primary biliary cirrhosis, and hepatic malignancy. Liver damage due to paracetamol overdose and partial hepatectomy both resulted in a striking increase in plasma PAI-1 concentration, although concentrations of t-PA and t-PA-PAI-1 complex were less affected. Concentrations of t-PA, PAI-1, and t-PA-PAI-1 complex returned to near normal values after successful liver transplantation in a patient with chronic active hepatitis. PAI-2 was also detected in several patients with chronic liver disorders. CONCLUSIONS--Haemorrhage due to fibrinolytic bleeding is commonly associated with liver disease. The patients studied here all had appreciable increases in circulating t-PA antigen concentrations. This was associated with increased concentrations of PAI-1 antigen and t-PA-PAI-1 complex and the balance between activator and inhibitor did not result in systemic plasmin generation. Reduced PAI-1 activity in cirrhosis or a critical difference in the ratio of t-PA to PAI-1 concentrations may explain the enhanced plasminogen activator activity previously noted in cirrhosis but not metastatic disease. Reduced hepatic clearance of t-PA and t-PA-PAI-1 complex due to impaired liver function may account for increased concentrations of free and complexed t-PA.     

Venous occlusion test: Assessment of fibrinolytic capacity by D-dimer latex agglutination test

The fibrinolytic capacity of 36 individuals was investigated by venous occlusion (VO) test. The specific components of fibrinolysis — plasminogen activator (t-PA) and plasminogen activator inhibitor activity (PAI) - were measured before and after 20 min VO and the subjects ,were divided into good (n=24) and poor (n=12) responders according to the presence of residual PAI activity after VO test. The ranking of the patients according to residual PAI activity correlated closely with that obtained by an index entitled the net fibrinolytic capacity (nFC) that expresses the ability of secreted t-PA to overcome PAI activity. Residual PAI and nFC were further compared with a recently published screening method based on fibrin degradation (D-dimer concentration) in a clotted blood sample obtained after VO. The D-dimer concentrations measured by a semiquantitative latex agglutination test agreed closely with the ranking of patients by residual PAI and nFC and had a close correlation with the concentrations of the specific components of fibrinolysis. We conclude that D-dimer test after 20 min VO qualifies well for screening of impaired fibrinolytic capacity.     

Fibrinolytic activity in the healthy newborn infant at term

At term, maternal plasma fibrinolytic activity is low secondary to high levels of fibrinolytic inhibitors, but in the newborn fibrinolytic activity has been reported to be increased. Venous blood was collected from 27 women with uncomplicated full-term pregnancies late in the second stage of labour. Cord venous blood samples were taken from the babies immediately after delivery. Plasminogen levels were increased in the maternal group and markedly decreased in the newborn group. Similarly, measurement of tissue plasminogen activator by immunological assay showed significantly higher levels in the mothers than in the neonates. In contrast, measurement of tissue plasminogen activator by functional assay showed significantly higher levels in the neonates than in the mothers.The apparent discrepancy in the t-PA function and IRMA results can be explained by the significantly higher levels of plasminogen activator inhibitor in the maternal plasma. The findings are in accordance with the greater overall fibrinolytic activity observed in neonatal than maternal plasma.     

卡托普利对家兔急性心肌梗塞早期血小板活化及纤溶活性的影响

本研究观察了家兔急性心肌梗塞（ＡＭＩ）早期血浆血小板α－颗粒膜蛋白（ＧＭＰ－１４０）、血栓素Ｂ２（ＴＸＢ２）、组织型纤溶酶酶原激活剂（Ｔ－ＰＡ）及其抑制物（ＰＡＩ－１）水平的变化及卡托利干预的ＰＡ活性显著降低；相关分析表明，血浆ＧＭＰ－１４０浓度与ＰＡＩ－１活性显著正相关。卡托普利干预后，血浆ＧＭＰ－１４０浓度、ＴＹＸＢ２浓度、Ｔ－ＰＡ浓度、ｔ－ＰＡ含量、ＰＡＩ－１活性均明显降低，而ｔ－ＰＡ活性显     

Fibrinolytic response after injection of desamino-d-arginine vasopressin (dDAVP) in healthy volunteers

The fibrinolytic response to desmopressin (dDAVP) given intravenously (i.v.) at 24-h intervals for 4 days and once subcutaneously (s.c.) 1 week later was studied in 6 healthy volunteers. The plasma levels of the tissue plasminogen activator (t-PA) activity were increased 10- to 20-fold and the t-PA antigen 2- to 3-fold, compared to the levels before i.v. injection. The PAI-1 concentration decreased after each i.v. injection and also following the s.c. injection.The t-PA response to s.c. and i.v. administration of dDAVP, measured as the area under the curve, was about the same. The plasma levels of fibrinopeptide A increased significantly after the first two i.v. and the s.c. dDAVP injections. No signs of decrease in the concentrations of plasminogen and antiplasmin were noted. In 37% of the observations, there was an increase in plasma D-dimers, indicating that the released t-PA induced a fibrin degradation. Whether the fibrinolytic response to dDAVP can be of any clinical relevance in a thrombotic situation remains to be investigated.     

Chronic glucocorticosteroid administration modulates the response of the fibrinolytic system to bacterial lipopolysaccharide

An in vivo rat model was used to study the effect of chronic glucocorticosteroid administration on the response of the fibrinolytic system to lipopolysaccharide (LPS). Male Lewis rats were injected subcutaneously for 30 consecutive days with either saline or saline containing 0.1 μg/g dexamethasone. On the thirty-first day, the rats were challenged with intraperitoneal injections of LPS (0.5 μg/g). Plasma and selected tissues (liver, kidney, heart, lung, muscle, and fat) were removed for analysis at various times after LPS injection. LPS treatment caused a rapid rise in plasma type 1 plasminogen activator inhibitor (PAW) activity in both groups. However, in the dexamethasone-pretreated animals a transient decline in PAI-1 activity was detected at 4 h, coinciding with a transient increase in plasma tissue plasminogen activator (t-PA) activity and a marked elevation of t-PA messenger RNA (mRNA) levels in the lung. Plasma t-PA activity returned below basal levels by 8 h and did not differ between the two groups at later times. At 24h, PAI-1 activity remained significantly elevated in the dexamethasone-pretreated rats while declining in the saline-pretreated rats. A greater induction of PAI-1 mRNA was evident in the dexamethasone-pretreated rats in all six tissues examined. Notably, a 3-fold greater increase in PAI-1 mRNA was detected in the liver at 24h, corresponding with the sustained elevation in plasma PAI-1 activity at this time. Collectively, these data suggest that chronic glucocorticosteroid treatment potentiates the induction of both t-PA and PAI-1 gene expression by LPS, resulting in an initial transient increase in plasma t-PA activity followed by a more sustained elevation in plasma PAI-1 activity.