Ethanol Increases Surface-Localized Fibrinolytic Activity in Cultured Endothelial Cells

Epidemiological studies demonstrated a positive association between moderate alcohol consumption and reduced cardiovascular mortality that may be mediated, in part, through increased fibrinolysis. These studies were conducted to determine whether low concentrations of alcohol (0.025 to 0.1%, v/v) directly affected the surface-localized versus secreted/solution phase fibrinolytic activity in live cultured endothelial cell (EC) types. Confluent live cultured ECs [human umbilical vein ECs (HUVECs), human saphenous vein ECs (HSVECs), and porcine aortic ECs (PAECs)] were preincubated (0 to 20 min, 4°C) in the absence or presence of varying concentrations of alcohol (0 to 0.1%, v/v), in the presence of saturating levels of ¹²⁵I-labeled Glu-plasminogen (2 μM) and ¹²⁵I-plasmin M_r 20-kDa light-chain formation quantitated by phosphorimaging autoradiography analysis. Endogenous plasminogen activator (PA)-mediated fibrinolytic activity was time- and dose-dependent; reached a maximum ?5- to 10-fold increase at 0.05% alcohol in HUVECs, HSVECs, and PAECs; was completely inhibited by anti-t-PA IgG in HUVECs; and partially inhibited by both anti-t-PA (?40%) and anti-u-PA IgG (?60%) in HSVECs. Complete inhibition of alcohol-induced (0.05%) fibrinolytic activity in cultured HUVECs by 2 mM tranexamic acid (an antagonist of plasminogen binding) indicated that the increased fibrinolytic activity was receptor-bound and localized to the EC surface, rather than present in or secreted into the medium (solution phase). Finally, the alcohol-induced increased fibrinolytic activity in cultured HUVECs returned to essentially normal control levels in ?1 hr. These studies have demonstrated a direct effect of low alcohol on EC fibrinolytic activity that may contribute, in part, to the decreased risk for thrombosis, coronary artery disease, and myocardial infarction associated with moderate alcohol consumption.     

冠心病患者血清甘油三酯水平与纤溶激活系统的关系

为研究冠心病患者血清甘油三酯水平与纤溶激活系统的关系,比较分析冠心病患者、高甘油三酯血症患者及正常对照者的血清甘油三酯水平、组织型纤溶酶原激活物及其抑制剂活性。纤溶酶原激活物抑制剂1、组织型纤溶酶原激活物活性测定采用发色低物法,血清甘油三酯浓度测定采用酶法。结果表明,高甘油三酯血症患者及冠心病患者纤溶酶原激活物抑制剂1活性较正常人升高,组织型纤溶酶原激活物活性较正常人下降。冠心病患者及高甘油三酯血症患者均有不同程度的纤溶活性下降,以急性心肌梗死、不稳定型心绞痛伴高甘油三酯组改变尤为明显。血清甘油三酯水平与血浆组织型纤溶酶原激活物活性呈负相关,与纤溶酶原激活物抑制剂1活性呈正相关。结果提示,甘油三酯通过影响纤溶功能参与冠心病的形成与发展。     

冠心病患者内皮祖细胞变化与冠状动脉病变的相关性

目的观察冠心病患者外周血中提取的内皮祖细胞的细胞形态、数量、集落数与正常对照组的区别。并研究冠心病患者冠状动脉狭窄的不同范围和程度与内皮祖细胞数量变化的相关性。方法选择冠心病患者57例和对照组30例,从外周血获取单个核细胞,体外培养后进行细胞分析和计数。并分析冠状动脉狭窄的不同范围和程度,患者内皮祖细胞数量和成集落数量的区别,并进行相关分析。结果 (1)冠心病患者外周血内皮祖细胞数量(23.1±1.8比56.7±2.4)和细胞集落数(14.7±2.5比24.2±1.7)较对照组明显减少;(2)随着冠状动脉狭窄范围的扩大和狭窄程度的加重,内皮祖细胞的数量和活性明显下降。结论冠心病患者外周血内皮祖细胞的数量和成集落的数量明显降低;冠心病患者外周血内皮祖细胞的数量与冠状动脉病变的范围和狭窄程度呈负相关。     

冠心病患者内皮祖细胞tPA和PAI表达的变化

目的探讨冠心病患者外周血中内皮祖细胞(EPC)的变化及其组织型纤溶酶原激活物(tPA)和纤溶酶原激活剂抑制剂(PAI)的表达。方法选择冠心病患者57例和对照组30例,提取内皮祖细胞进行数量和细胞集落的比较。利用ELISA法和底物发光法检测EPC分泌tPA和PAI的浓度和活性;用RT-PCR法检测EPC的tPA和PAI mRNA表达。结果冠心病患者EPC数量较对照组明显减少(23.1±1.8比56.7±2.4,P<0.05),形成细胞集落数(14.7±2.5比24.2±1.7,P<0.05)、细胞增殖能力也明显降低,冠心病患者EPC的tPA表达较对照组下降,PAI表达增强。结论冠心病患者外周血EPC数量减少和功能障碍可能在疾病的发生发展中起作用。     

血管内皮功能障碍在冠心病发生发展中的作用

在冠状动脉的动脉粥样硬化发生发展的过程中,内皮受损及内皮功能失调不仅是始动因素之一,也是其发展和转归中的重要环节。本文旨在通过对现有内皮功能与冠心病相关研究的分析来阐述内皮功能障碍在冠状动脉粥样硬化的始动、发生发展及心血管事件中的作用。     

Human Tissue Kallikrein Activity in Angiographically Documented Chronic Stable Coronary Artery Disease

Background

Human tissue kallikrein (hK1) is a key enzyme in the kallikrein–kinin system (KKS). hK1-specific amidase activity is reduced in urine samples from hypertensive and heart failure (HF) patients. The pathophysiologic role of hK1 in coronary artery disease (CAD) remains unclear.

Objective

To evaluate hK1-specific amidase activity in the urine of CAD patients

Methods

Sixty-five individuals (18–75 years) who underwent cardiac catheterism (CATH) were included. Random midstream urine samples were collected immediately before CATH. Patients were classified in two groups according to the presence of coronary lesions: CAD (43 patients) and non-CAD (22 patients). hK1 amidase activity was estimated using the chromogenic substrate D-Val-Leu-Arg-Nan. Creatinine was determined using Jaffé’s method. Urinary hK1-specific amidase activity was expressed as µM/(min · mg creatinine) to correct for differences in urine flow rates.

Results

Urinary hK1-specific amidase activity levels were similar between CAD [0.146 µM/(min ·mg creatinine)] and non-CAD [0.189 µM/(min . mg creatinine)] patients (p = 0.803) and remained similar to values previously reported for hypertensive patients [0.210 µM/(min . mg creatinine)] and HF patients [0.104 µM/(min . mg creatinine)]. CAD severity and hypertension were not observed to significantly affect urinary hK1-specific amidase activity.

Conclusion

CAD patients had low levels of urinary hK1-specific amidase activity, suggesting that renal KKS activity may be reduced in patients with this disease.     

稳定型冠心病患者血浆内皮微粒与动脉弹性的关系

目的研究稳定型冠心病患者血浆内皮微粒(EMP)水平与肱踝脉搏波传导速度(baPWV)之间的关系。方法选择稳定型冠心病患者50例和健康志愿者20例,采用流式细胞术检测两组患者血浆中EMP(CD31+/CD42b-)水平,同时应用无创动脉硬化检测装置测定baPWV,探讨二者之间的关系。结果冠心病组患者血浆EMP水平较对照组显著升高(1 748.4±102.1个/微升比847.4±86.4个/微升,P<0.01);冠心病组患者baPWV较对照组增快(1 931.1±328.3 cm/s比1 532.1±147.3 cm/s,P<0.01)。血浆EMP水平与baPWV呈正相关(r=0.42,P<0.01)。以baPWV为因变量的多因素回归分析显示,血浆EMP水平是其独立影响因素。结论稳定型冠心病患者血浆EMP水平升高,baPWV加快且与EMP水平呈正相关,血浆EMP水平是baPWV的独立影响因素。     

冠心病患者外周血内皮祖细胞的数量和活性

目的研究冠心病患者外周血中内皮祖细胞的数量、形态和活性。方法选择冠心病患者57例和正常对照者30例,用密度梯度离心法从外周血获取单个核细胞,将其接种在人纤维连接蛋白包被的培养板,用加入血管内皮生长因子165和碱性成纤维细胞生长因子的1640培养基培养细胞,并分析细胞形态和形成集落的数量,7d后贴壁细胞进行细胞分析和计数。用激光共聚焦显微镜鉴定FITC标记的荆豆凝集素和Dil标记的乙酰化低密度脂蛋白,双染色阳性细胞为正在分化的内皮祖细胞;用流式细胞仪检测细胞表面抗原CD34和KDR;采用MTT比色法检测细胞的生长状态。结果冠心病患者外周血内皮祖细胞数量较对照组明显减少(23.1±1.8个/200倍比56.7±2.4个/200倍,P<0.05),形成细胞集落数(14.7±2.5个/40倍比24.2±1.7个/40倍,P<0.05)、细胞增殖能力和生长曲线也明显降低。结论冠心病患者外周血内皮祖细胞的数量和活性明显降低。     

Activation of Plasma Prorenin by Plasminogen Activators in Vitro and Increase in Plasma Renin After Stimulation of Fibrinolytic Activity in Vivo

Plasminogen can be activated by intrinsic activators that circulate in plasma in a precursor form, by extrinsic activator originating from tissues or the vessel wall and by the exogenous activators, urokinase and streptokinase. Tissue activator and vascular activator are probably identical. Dialysis of plasma against pH 4.0 buffer causes denaturation of the plasmin inhibitors, α₂-antiplasmin and C1-inhibitor, while α₂-macroglobulin is left intact. Incubation of pH 4.0-pretreated plasma with urokinase or streptokinase at pH 7.5 led to activation of plasminogen and prorenin. Incubation of a plasma fraction, which contained plasminogen and prorenin but no α₂-antiplasmin and renin, with highly purified tissue plasminogen activator also led to activation of prorenin. The vasopressin analogue, 1-des-amino-8-D-arginine vasopressin (DDAVP), is a potent stimulant for the release of extrinsic activator into the bloodstream. After infusion of DDAVP, 0.4 μg/kg, into normal subjects, parallel increments in plasma fibrinolytic activity and renin were observed. Infusion of DDAVP into patients with type IV hyperlipoproteinaemia had little effect on plasma fibrinolytic activity and the response of plasma renin was also subnormal. These observations warrant further studies on a possible role for plasminogen activators in prorenin activation in vivo.     

内源性雌激素对血管内皮功能的作用

为探讨内源性雌激素对女性冠心病患者血管内皮功能的作用及其可能机制 ,采用高分辨力超声法测定33例女性冠心病患者和 17例对照者血流介导的肱动脉舒张反应 ,用双抗体放射免疫法测定血浆雌二醇水平 ,高效液相色谱仪测定血浆非对称性二甲基精氨酸含量。结果发现 ,冠心病患者血流介导的肱动脉舒张反应明显低于对照者 (1.73%± 1.2 6 %比 5 .37%± 3.2 0 % ,P <0 .0 0 1) ,冠心病患者雌二醇水平也明显低于对照者 (2 7.80± 12 .2 8ng L比 4 3.83± 14 .30ng L ,P <0 .0 1) ,而冠心病患者非对称性二甲基精氨酸水平明显高于对照者 (3.39± 1.0 7μmol L比1.31± 0 .6 9μmol L ,P <0 .0 0 1)。血流介导的肱动脉舒张反应与雌二醇水平呈正相关 (β =0 .314 ,P <0 .0 5 ) ,与非对称性二甲基精氨酸水平呈负相关 (β=- 0 .30 2 ,P <0 .0 5 ) ,且雌二醇水平与非对称性二甲基精氨酸呈独立负相关 (r=- 0 .5 4 4 ,P <0 .0 0 1)。结果提示 ,女性冠心病患者血管内皮依赖性舒张功能降低。内源性雌激素水平的降低及其所伴随的非对称性二甲基精氨酸水平增高对女性冠心病患者血管内皮功能有损害作用。     

冠心病患者血浆脂蛋白(a)浓度与组织型纤溶酶原激活剂及抑制物活性的关系

为了了解冠心病患者血浆脂蛋白（a）浓度与组织型纤维蛋白溶解酶原激活剂及其抑制物活性的关系，进一步研究脂蛋白（a）促血栓形成的机理，本文应用酶联免疫吸附法测定20例冠心病患者与20名健康人脂蛋白（a）浓度，并以底物显色法测定其血浆组织型纤维蛋白溶解酶原激活剂及其抑制物活性。结果发现，冠心病组血脂蛋白（a）浓度和纤维蛋白溶酶原激活剂抑制物活性显著高于对照组，而纤维蛋白溶解酶原激活剂活性显著低于对照组；两组脂蛋白（a）浓度与纤维蛋白溶解酶原激活剂活性无关，而与纤维蛋白溶解酶原激活剂抑制物活性呈显著正相关。提示血浆高脂蛋白（a）浓度是冠心病的危险因素，冠心病患者纤溶与凝血功能失去平衡，促进了冠状动脉内血栓形成与动脉硬化的发展，进而导致和加重冠心病。     

冠心病患者血浆脂蛋白(a)浓度与组织型纤溶酶原激活剂及抑制物活性的关系

为了了解冠心病患者血浆脂蛋白(a)浓度与组织型纤维蛋白溶解酶原激活剂及其抑制物活性的关系,进一步研究脂蛋白(a)促血栓形成的机理,本文应用酶联免疫吸附法测定20例冠心病患者与20名健康人脂蛋白(a)浓度,并以底物显色法测定其血浆组织型纤维蛋白溶解酶原激活剂及其抑制物活性。结果发现,冠心病组血脂蛋白(a)浓度和纤维蛋白溶酶原激活剂抑制物活性显著高于对照组,而纤维蛋白溶解酶原激活剂活性显著低于对照组;两组脂蛋白(a)浓度与纤维蛋白溶解酶原激活剂活性无关,而与纤维蛋白溶解酶原激活剂抑制物活性呈显著正相关。提示血浆高脂蛋白(a)浓度是冠心病的危险因素,冠心病患者纤溶与凝血功能失去平衡,促进了冠状动脉内血栓形成与动脉硬化的发展,进而导致和加重冠心病。     

Synthesis and Release of Factor VIII by Cultured Human Endothelial Cells

Endothelial cells (ECs) derived from human umbilical veins were cultured in order to study the physiological control of factor VIII synthesis and release. The culture media were studied from multiple replicate cultures at confluence. Factor VIII related antigen (VIIIR:Ag) and factor VIII coagulant antigen (VIII:CAg) were measured by sensitive immunoradiometric assays. De novo synthesis of factor VIII related protein (VIII:R) was quantitated by incorporation of labelled amino acids into specific protein subunits. The following agents were added to the culture medium in a range of concentrations from physiological to pharmacological: adrenaline, 5 hydroxytryptamine, 2,3-DPG, cyclic AMP, thyroxine, hydrocortisone, and human growth hormone. None of them had any effect at any concentration on the rate of accumulation of VIIIR:Ag in the culture medium. Addition of exogenous factor VIII had no effect on do novo synthesis of VIII:R. VIII:CAg was found to be stable under the conditions of culture but none was released from the ECs. Long-term monocyte cultures also failed to release VIII:CAg. It appears that VIII:R is a constitutive gene product of umbilical vein endothelial cells and that VIII:CAg is not made by these cells.     

脑梗死患者血浆组织型纤溶酶原激活物和抑制物活性的变化及意义

为了探讨动脉硬化性脑梗死患者急性期和恢复期的组织型纤溶酶原激活物及其抑制物活性的变化及其意义,采用发色底物法检测9例脑梗死患者和40例健康老年人的血浆组织型纤溶酶原激活物和抑制物1活性.对脑梗死患者的梗死体积和神经功能缺损进行了计算和评分,结果发现,脑梗死组急性期和恢复期的组织型纤溶酶原激活物活性分别为0.26±0.14和0.21±0.11 kIU/L,显著低于健康组(P<0.01);纤溶酶原激活物抑制物1活性分别为0.90±0.25和0.98±0.12 kAU/L,显著高于健康组(P<0.01);脑梗死体积为8.75±1.21 cm3;急性期神经功能缺损评分为18.56±3.62;组织型纤溶酶原激活物活性与脑梗死体积和神经功能缺损程度负相关(r=-0.5133,JP<0.05;r=-0.4914,P<0.05),纤溶酶原激活物抑制物1活性与脑梗死体积和神经功能缺损程度正相关(r=0.5621,P<0.05;r=0.5342,P<0.05)。结果提示,脑梗死患者急性和恢复期血浆纤溶活性显著降低,提示组织型纤溶酶原激活物与抑制物1在动脉硬化性脑梗死的病理过程中发挥了重要的作用。     

内皮型一氧化氮合酶在冠状动脉粥样硬化性心脏病的作用

一氧化氮合酶包括三种亚型(内皮型,诱导型,神经型),内皮型一氧化氮合酶合成体内一氧化氮,在冠状动脉粥样硬化性疾病的发生发展中起着重要的作用。三种亚型的一氧化氮合酶全部缺失的大鼠会发生自发性心梗。病例对照和前瞻性研究都证实内皮型一氧化氮合酶的基因多态性与冠心病相关,突变型携带者(TT型,rs2070744)比其他基因型者会有较高的患冠心病甚至心血管病死亡的风险。     

冠心病高脂血症患者L-精氨酸、硝酸根、亚硝酸根及组织型纤溶酶原激活物水平的变化

观察30例冠心病高脂血症患者和16例正常人脂过氧化物、L-精氨酸、硝酸根、亚硝酸根、组织型纤溶酶原激活物和纤溶酶原激活物抑制剂水平的变化。结果发现,冠心病高脂血症患者L-精氨酸水平、组织型纤溶酶原激活物和超氧化物歧化酶活性下降(与对照组相比,p<0.05),硝酸根、亚硝酸根及脂过氧化物水平升高(p<0.05)。结果提示冠心病高脂血症患者血浆中L-精氨酸相对缺乏,可能与其一氧化氮需要量增加有关;血清中硝酸根和亚硝酸根的含量增加,可能与一氧化氮的降解增加有关;组织型纤溶酶原激活物活性降低可能与细胞功能障碍有关。     

心力衰竭患者血浆纤溶活性指标的变化及福辛普利的干预作用

目的:探讨心力衰竭患者血浆纤溶活性指标的变化以及血管紧张素转换酶抑制剂福辛普利干预的影响。方法:58例心力衰竭患者随机分成福辛普利组30例和常规治疗组28例,福辛普利组在常规治疗基础上加用福辛普利10mg/d,入院后当天和治疗后2周采血检测血浆纤溶酶原激活剂抑制物1(PAI1)含量与活性、组织纤溶酶原激活剂(tPA)活性。选择20例健康体检者作为正常对照。结果:与健康体检者比较,心力衰竭患者血浆PAI1含量与活性升高,tPA活性降低(P均<0.01);治疗后2周福辛普利组较常规治疗组血浆PAI1含量与活性明显降低(P均<0.01),tPA活性明显升高(P均<0.01)。结论:心力衰竭时血浆纤溶活性降低,福辛普利治疗可改善其纤溶活性,对降低心力衰竭患者血栓栓塞性疾病的发生可能有重要意义。