睾酮对人血管内皮细胞纤溶活性影响及机制

目的：观察睾酮对人血管内皮细胞分泌纤溶酶原激活物（tPA）、纤溶酶原激活物抑制物1（PAI-1）的影响及其机制。方法： 将体外培养的人血管内皮细胞（HUVEC）分为5个浓度睾酮组及单纯培养基对照组，MTT实验观察睾酮对细胞生长及活性影响。ELISA 法测各组tPA、 PAI-1含量。用雄激素受体拮抗剂(flutamide)预处理细胞后重复实验。结果： 生理及略低于生理剂量睾酮（3×10-10 mol/L-3×10-8 mol/L）可明显促进tPA 分泌（P＜0.01）；而大剂量则使tPA 含量明显减少（P＜0.01）。各睾酮组PAI-1含量均明显低于对照组（P＜0.05）。Flutamide 能有效消除睾酮的上述作用。结论： 生理浓度睾酮通过雄激素受体促进tPA分泌，降低PAI-1浓度而增强纤溶系统活性，有利于防止血栓性疾病的发生。     

辛伐他汀对尼古丁诱导脐静脉 内皮细胞分泌t-PA和PAI-1的影响

目的: 研究不同浓度辛伐他汀对尼古丁诱导人脐静脉内皮细胞(HUVECs)分泌组织纤溶酶原激活物(t-PA)和1型纤溶酶原激活物抑制剂(PAI-1)及其基因表达的影响。方法: 将3-6代体外培养的HUVECs随机分为对照组、尼古丁组及不同浓度辛伐他汀组,辛伐他汀组分别以1、10、100 μmol/L辛伐他汀预处理细胞2 h,再以100 μmol/L尼古丁孵育24 h。酶联免疫吸附双抗体夹心法(ELISA)检测细胞上清液t-PA和PAI-1含量;逆转录聚合酶链反应(RT-PCR)检测细胞t-PA和PAI-1 mRNA的表达。结果: 尼古丁组PAI-1分泌和mRNA表达较对照组显著升高(P<0.05)。不同浓度辛伐他汀组PAI-1分泌和mRNA表达均较尼古丁组显著降低,且PAI-1分泌和mRNA表达的降低呈浓度依赖性(均P<0.05),以100 μmol/L辛伐他汀组最为显著。100 μmol/L辛伐他汀组PAI-1分泌和mRNA表达与对照组比较,无显著差异(P>0.05)。尼古丁组t-PA mRNA表达较对照组显著降低(P<0.05)。10、100 μmol/L辛伐他汀组t-PA mRNA表达较尼古丁组显著升高(P<0.05),各组间t-PA分泌无显著差异(均P>0.05)。结论: 在体外,辛伐他汀可降低尼古丁所致的PAI-1分泌和mRNA的表达,并升高t-PA mRNA的表达,从而逆转尼古丁介导的HUVECs纤溶活性减低。     

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。     

LPS促进HUVECs表达纤溶酶原激活物抑制物1

目的：观察LPS对脐静脉血管内皮细胞(HUVECs)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： 用生长良好的第2、3代HUVECs进行试验。用cell counting kit-8(CCK-8)测定LPS刺激后细胞活性变化；发色底物法测定LPS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： 与对照组相比，LPS(10 mg/L)对细胞活性没有明显差异。LPS诱导PAI-1活性在24-72 h显著升高(P<0.05),且显著上调PAI-1 mRNA，24 h达到峰值，以后渐降，72 h达到正常水平。而LPS组与对照组tPA活性与tPA mRNA无明显差异(P>0.05)。 结论： LPS(10 mg/L)可显著上调PAI-1 mRNA转录和分泌而不影响tPA mRNA，结果提示LPS可活化内皮细胞，诱发PAI-1 mRNA表达和蛋白分泌而抑制纤溶系统，这有利于微血栓的形成、血栓稳定,血液凝固和DIC发生。     

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。     

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。     

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,     

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。     

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。     

锡类散凝胶对兔输液性静脉炎治疗效果的初步观察

目的探讨锡类散凝胶对兔实验性输液性静脉炎的治疗效果及可能机制。方法将大白兔随机分为对照组、静脉炎组和锡类散治疗组，每组20只。静脉炎组在耳缘静脉注射甘露醇构建实验眭输液性静脉炎动物模型，对照组以生理盐水替代甘露醇，治疗组在造模前经锡类散预处理；在造模后相应的时间点检测兔血浆中TT（凝血酶时间）、PT（凝血酶原时间）、APTT（活化部分凝血酶时间）、PAI-1（I型纤溶酶原激活物抑制因子）和t—PA（组织型纤溶酶原激活剂）含量，并作病理学检查及评分，最后进行统计分析。结果治疗组与静脉炎组相比较（P〈0．05），能明显纠正因甘露醇而造成的高凝状态，有效降低血清t—PA水平及减轻输液静脉损害；而PAI—1含量在三组之间没有统计学差异（P〉0．05）。结论锡类散凝胶能有效改善甘露醇所致的输液胜静脉炎损害，其机制可能通过抑制血清t—PA升高而发挥治疗作用。     

中药对脑栓塞患者抗血栓作用的研究

目的 :研究中药对风心脑栓塞患者的抗血栓作用。方法 :测定 31例风心脑栓塞患者 (男 18,女13) ,平均年龄 5 6± 8岁 ,运用加减桃红四物汤 ,对治疗前后血中抗凝和纤溶方面指标进行测定。同时测定 30例正常人血指标 (男 19,女 11) ,平均年龄 5 4± 4岁 ,所有病人服药 14天。结果 :用药后纤溶酶原 (PLG)、纤溶酶原活化素灭活剂 (PAI)比用药前下降 (p <0 0 5 )。AT -Ⅲ :A ,AT -Ⅲ :Ag ,tPA及D二聚体 (D -dimer)比用药前增加 (p <0 0 5 )。结论 :桃红四物汤具有一定抗凝作用 ,促进微血栓的纤溶过程 ,在风心脑栓塞患者的治疗中有一定价值     

肾上腺素对大鼠肢体血管壁释放纤溶酶元活化素的作用

本文利用大鼠下肢血管灌流模型、纤维蛋白平板纤溶测定及纤维蛋白自显影技术,研究肾上腺素对血管壁释放纤溶酶元活化素(PA)的影响。结果表明,25μM肾上腺索诱导PA活力明显增加,经鉴定这种肾上腺素所诱导释放的PA是分子量为67000道尔顿、组织类型的纤溶酶元活化素(t-PA),这种PA释放作用能为β受体拮抗剂心得安阻断,外源性cAMP能模仿肾上腺素的这一作用。提示肾上腺素诱导t-PA释放作用可能部分通过β肾上腺能受体介导,经cAMP增加的途径。     

肝素对大鼠Thy-1肾炎u-PA/PAI-1表达的影响

目的：研究尿激酶型纤溶酶原激活物／Ⅰ型纤溶酶原激活物抑制因子（u-PA/PAI-1)在大鼠Thy-1肾炎病变进展过程中的变化，以及肝素对其表达的影响。方法：以抗Thy-1单抗成功制备大鼠Thy-1肾炎模型，并用肝素对其进行治疗，分别于1、3、7、14、21、28d处死动物并分别取其肾皮质。应用RT－PCR及Western blot方法检测肾皮质u-PA/PAI-1 mRNA及蛋白表达的变化，以观察肝素对其表达的影响。结果：RT－PCR法显示肾炎模型组（G组）于3－28d的肾皮质u-PA mRNA和3－21d的肾皮质PAI－1 mRNA的表达均高于对照组（P＜0.05或P＜0.01)；肝素治疗组（H组）仅21d时肾皮质u-PA mRNA的表达高于G组（P＜0.05)，而PAI-1 mRNA的表达于3－28d时均低于G组（P＜0.05)。Western blot结果显示3－28d时，G组u-PA和PAI－1蛋白表达量高于对照组（P＜0.05或P＜0.01)，这与RT－PCR检测结果相似；H组肾皮质u-PA蛋白表达量与G组相比差异无显著性，而3－21d时PAI－1蛋白表达量均低于G组（P＜0.05或P＜0.01)。结论：大鼠Thy-1肾炎肾皮质u-PA与PAI－1的表达均随肾小球病变的进展而增强，肝素治疗可能通过干扰或抑制u-PA和PAI－1的表达而发挥其治疗作用。     

uPA系统与神经胶质瘤局部侵袭

uPA系统包括尿激酶型纤溶酶原激活物（urokinase plasminogen activator, uPA）、 尿激酶型纤溶酶原激活物受体（urokinase plasminogen activation receptor, uPAR）和纤溶酶原激活物抑制剂(plasminogen activator inhibitor, PAI),它们参与了多种人类恶性肿瘤的局部侵袭和转移,是目前肿瘤治疗重要的分子靶点。uPA能激活纤溶酶原降解细胞外基质与基底膜,uPAR则能显著提升uPA的激活纤溶酶原的功能,两者结合能够增强肿瘤的侵袭性与转移能力。PAI主要通过促进血管内皮生长因子（vascular endothelial growth factor,VEGF）的表达,促进新生血管的形成,从而促进肿瘤的局部侵袭,但PAI又可通过抑制uPA-uPAR复合体的生物学活性来抑制肿瘤的局部侵袭。神经胶质瘤是最常见的颅内肿瘤,很少转移到颅外,局部侵袭是其预后不良的主要原因。近年来发现uPA系统的表达水平与神经胶质瘤的恶性程度呈正相关。本文综述了uPA系统对神经胶质瘤局部侵袭的影响及其在治疗中的意义。     

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     

Plasminogen Activators and Their Inhibitor in Bone Tumors and Tumor-Like Damages

Expression of urokinase- and tissue-type plasminogen activators and their inhibitor PAI-1 in the cytosolic fraction of 20 osteosarcomas, 20 chondrosarcomas, 13 giant-cell bone tumors, 5 Ewing's sarcomas, and 7 osteochondral exostoses was studied by enzyme immunoassay. The content of urokinase-type plasminogen activator increased, while the concentration of tissue-type plasminogen activator decreased in bone tumors of various histological compositions compared to osteochondral exostoses. A positive correlation was found between PAI-1 content and the volume of osteo- and chondrosarcomas. Expression of urokinase-type plasminogen activator increased in patients with primary osteosarcomas characterized by early generalization of the pathological process.     

The urokinase plasminogen activator (u-PA) and its inhibitor (PAI-1) in embryo-fetal bone formation in the human: an immunohistochemical study

The role of urokinase plasminogen activator and plasminogen activator inhibitor-1 in human embryofetal bone formation between the 9th and the 20th week of gestation has been studied immunohistochemically. While mature osteocytes of the secondary spongiosa and resting chondrocytes of the bone epiphyses were negative for both antigens in each developmental stage, metabolically active parts of the osseocartilaginous system showed a strong immunoreactivity. Until the end of the 10th week of gestation urokinase plasminogen activator and plasminogen activator inhibitor-1 could not be demonstrated in the shaft of the preexisting cartilaginous models of bones, which correlates with the morphological developmental stage of the embryos. Later, osteoblasts and chondrocytes in the areas of enchondral ossification, and the perivascular chondrocytes of the epiphyseal secondary ossification centres, showed similarly high concentrations of urokinase plasminogen activator and plasminogen activator inhibitor-1. Moreover, the individual ossification stages of the different bones in embryo-fetal development could be demonstrated immunohistochemically. While humeri and femora showed diaphyseal immunoreactivities at an early stage, positive reactions in the phalanges were found only much later. Thus, the enzymes of the fibrinolytic system studied are clearly involved in the desmal and enchondral ossification process in the osseocartilaginous compartment.     

The effect of different exercise intensities on the fibrinolytic system

Summary The effects of moderate 30-min cycle ergometer exercise (aerobic metabolism) followed by short-term exercise at maximal capacity (anaerobic metabolism) on fibrinolytic activity were investigated in ten female and ten male healthy, untrained subjects. The following parameters of fibrinolytic activity were measured initially (t ₀), at the end of the aerobic phase (t ₁), at the end of the anaerobic phase (t ₂) and after a 30-min recovery period (t3): tissue plasminogen activator (PA_t) activity, PA_t concentration, plasminogen activator inhibitor (PA_i) activity, and D-Dimer concentration. Moderate long-term exercise caused a slight but significant increase in PA_t concentration and PA_t activity (t ₁; P<0.01), whereas short-term exercise at maximal capacity (t ₂) produced a substantial elevation in both these parameters (P<0.01). This would suggest that PAt was not inhibited totally by PA_i which would itself seem to be consumed during exercise. In addition, a slight exercise intensity-dependent increase in D-Dimer concentration was measured — circumstancial evidence not only for elevated fibrinolytic potential, but also for an actual increase in fibrin degradation (t ₂: P<0.01). After t ₃ both PA_t activity and D-Dimer concentration were still slightly but significantly increased. The results obtained in the tests of fibrinolytic activity showed no significant difference between the men and the women. It would seem that the release of PA_t is more markedly stimulated by short-term intense physical exercise than by long-term moderate exercise and actually causes increased fibrin degradation.     

Tissue-type plasminogen activator and its inhibitor in human glomerulonephritis.

We carried out an immunohistochemical study of tissue-type plasminogen activator (PA) and urokinase-type PA, and their inhibitors, PA inhibitor-1 and PA inhibitor-2, using renal biopsy specimens obtained from 86 patients with various forms of glomerulonephritis. The controls were four normal renal tissue specimens. On immunofluorescent observation, granular staining for tissue-type PA was found to be distributed along the glomerular capillary walls. The fluorescence was weak in the normal renal tissue and occasionally intense in the tissues of patients with IgA nephritis, minimal change nephrotic syndrome, and lupus nephritis. PA inhibitor-1 was abundant in the glomerular epithelial cells and scarce in the mesangial area and glomerular capillary lumens of the normal renal tissues. This was confirmed by immunoelectron microscopy using gold staining. The fluorescence of PA inhibitor-1 was weaker in some specimens of nephritic tissues than in the normal renal tissues. Urokinase-type PA and PA inhibitor-2 were negative within the glomeruli in all the specimens. In the glomerulonephritic tissues which were fibrin deposition-positive, tissue-type PA expression in the glomeruli tended to be strong. An association between fibrin deposition and PA inhibitor-1 staining was not clear. These data suggest that expression of tissue-type PA in the glomeruli increases in association with fibrin deposition.