长球囊介入治疗对老年糖尿病足患者纤溶及凝血系统的影响

目的 探讨长球囊介入治疗对老年糖尿病足患者纤溶及凝血系统的影响.方法 2007年2月至2012年2月分别采用长球囊血管成形术和短球囊血管成形术治疗糖尿病足患者,比较两组患者治疗前后组织型纤溶酶原激活物(t-PA)、溶酶原激活物抑制剂-1(PAI-1)及纤维蛋白肽A(FPA)等纤溶及凝血相关指标的动态变化.结果 研究组患者的球囊直径、球囊长度及球囊扩张次数与对照组比较有明显差异(t=3.45、18.76、8.94,P＜0.05).研究组和对照组患者在术后即刻t-PA含量均明显下降(P＜0.05),而两组间比较则无明显差异(P＞0.05);在术后24 h,研究组t-PA含量较本组术后即刻及对照组均明显上升,恢复至术前水平(t=5.32,P＜0.05).两组患者术后即刻FPA、PAI-1含量均较本组术前明显上升(t =3.95、3.86、4.21、4.82,P＜0.05);而在术后24 h两组PAI-1含量与本组术后即刻相比较明显下降(t=4.25、4.38,P＜0.05),而且研究组在术后24 h与同期的对照组相比下降更明显(t=3.01、3.17,P＜0.05);两组患者术后24 h FPA含量也明显下降(t=3.11、3.84,P＜0.05),与术前FPA水平相接近.结论 长球囊血管成形术可以降低术后血栓事件发生率,预防术后再狭窄率低,即长球囊血管成形术可增强纤溶系统活性,减弱凝血系统活性.     

氯沙坦对扩张型心肌病心力衰竭患者纤溶参数的影响

目的了解扩张型心肌病心力衰竭患者纤溶参数的变化,及氯沙坦对纤溶参数的影响.方法测定40名健康者和60例扩张型心肌痛心衰患者血浆纤溶酶原激活物(tPA)活性,纤溶酶原激活物抑制物-1(PAI-1)活性以及血管紧张素Ⅱ(AngⅡ)含量.将扩张型心肌病患者随机分成常规治疗组和氯沙坦组.治疗14天后复查tPA、PAI-1、AngⅡ. 结果与正常对照组相比,扩张型心肌病心衰患者tPA活性下降、PAI-1活性升高、AngⅡ含量上升(P＜0.01).治疗14天后,常规治疗组tPA与PAI-1的活性和AngⅡ含量无显著变化(P＞0.05);氯沙坦组tPA活性上升、PAI-1活性下降(P＜0.01),AngⅡ含量降低(P＜0.05).结论扩张型心肌痛心力衰竭患者纤溶参数明显异常,氯沙坦能改善纤溶参数活性.     

肺原性心脏病心力衰竭患者的凝血纤溶系统活性变化

目的探讨肺原性心脏病(肺心病)充血性心力衰竭患者凝血纤溶指标的变化及意义。方法测定肺心病充血性心力衰竭患者组织型纤溶酶原激活物(tPA)活性、纤溶酶原激活物特异性抑制物(PAI-1)活性和D-二聚体(DD)含量。结果肺心病心力衰竭组血浆tPA活性较健康对照组降低,而PAI-1活性、DD含量明显升高。不同心功能等级的肺心病心力衰竭患者血浆PAI-1活性、DD含量随着心功能程度的加重而明显升高。结论肺心病充血性心力衰竭患者存在凝血纤溶活性异常,且与心功能程度有关。     

血管紧张素转换酶抑制剂对糖尿病大鼠血浆PAI-1和tPA活性的影响

目的 探讨血管紧张素转换酶抑制剂(ACEI)对糖尿病(DM)大鼠血浆纤溶酶原激活物抑制剂1(PAI-1)和组织型纤溶酶原激活物(tPA)活性的影响及其机制.方法 将链脲佐菌素诱导的DM大鼠分为正常对照组、培哚普利治疗组、培哚普利联合一氧化氮合酶(NOS)抑制剂治疗组.治疗4周后比较各组血浆PAI-1和tPA活性及PAI-1/tPA比值.结果 与正常对照组相比,DM大鼠血浆PAI-1活性和PAI-1/tPA比值显著升高,tPA活性降低.培哚普利治疗使PAI-1活性下降,tPA活性增加.联合NOS抑制剂在一定程度上抵消了培哚普利的这种作用.结论 DM状态下存在纤溶异常,ACEI能够通过内源性的NO改善纤溶平衡.     

L—精氨酸对动脉损伤后血浆α颗粒膜蛋白、纤溶活性和动脉内膜增生影响的实验研究

采用兔髂动脉球囊内皮剥脱术建立血管成形术动物模型,观察一氧化氮(NO)的前体L一精氨酸(L-Arg)对动脉损伤后血浆α颗粒膜蛋白(GMP-140)、组织型纤溶酶原激活物(tPA)、纤溶酶原激活物抑制物(PAI-1)的动态变化和动脉新生内膜形成的影响.结果表明,对照组术后6h、24h、48h血浆GMP-140活性明显高于正常水平,并于24h达到高峰,1周回到基础值;同时tPA活性明显受到抑制,PAI-1活性升高.L-Arg可显著降低血浆GMP-140活性,并伴有tPA升高,PAI一1下降(两组比较P<0.05或P<0.01).4周后动脉新生内膜面积、新生内膜面积/中膜面积比值明显降低(两组比较P<0 .01).提示L一Arg可明显抑制动脉损伤后血小板的活化,激活纤溶系统,使动脉中层平滑肌细胞的增殖减轻,达到降低新生内膜形成的目的.     

介入封堵术对成人先天性心脏病患者血浆t-PA和PAI-1水平的影响

目的评价介入封堵术对成人先天性心脏病(CHD)患者血浆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)水平的影响.方法采用酶联免疫吸附法检测70例CHD患者及30例健康人(正常对照组)血浆t-PA、PAI-1水平.所有CHD患者分别于介入封堵术前头天,术后24 h,1、3、6、12个月检测血浆t-PA、PAI-1水平.结果介入封堵术前,CHD患者血浆t-PA、PAI-1水平比正常对照组明显增高(P＜0.01).介入封堵术后1个月,CHD组血浆PAI-1水平开始逐渐下降,术后6个月恢复正常水平;血浆t-PA水平在术后1个月升高,术后3个月始下降,术后6个月恢复正常水平.结论介入封堵术可通过改变血浆t-PA、PAI-1水平而改善成人CHD患者的内源性纤溶功能.     

氯沙坦对高血压病人血压、凝血和纤溶活性的影响

目的观察高血压病人凝血和纤溶活性的改变,探讨血管紧张素Ⅱ受体拮抗剂氯沙坦对高血压病人血压以及凝血和纤溶系统的影响.方法将26例原发性高血压病人和30例正常对照组进行比较.所有入选对象1个月内未服任何降脂药物,停用降压药1周以上,禁食10h后,次晨抽取血样,测定各项指标.结果高血压病人胰岛素敏感性指数(ISI)和组织型纤溶酶原激活物(tPA)水平降低,而纤溶酶原激活物抑制剂-1(PAI-1)活性和血管性血友病因子(vWF)则升高.经多元逐步回归分析提示PAI-1与收缩压水平、总胆固醇和vWF呈显著正相关.高血压组给予氯沙坦50～100mg/d治疗,疗程6周,收缩压和舒张压明显下降;PAI-1活性较治疗前明显降低;而tPA活性较治疗前升高;ISI和vWF在治疗后无明显变化.结论高血压病人存在一定程度的胰岛素抵抗和凝血、纤溶功能紊乱.氯沙坦治疗能有效降低病人的血压,同时可以改善高血压病人的纤溶活性.     

小剂量尿激酶治疗不稳定性心绞痛对凝血、纤溶活性和血小板聚集的影响

目的在小剂量尿激酶溶栓治疗不稳定性心绞痛中,探索溶栓前充分抗凝和抗血小板与否对血浆纤维蛋白肽A(FPA)、凝血烷B2(TXB2)、组织纤溶酶原激活物(t-PA)和纤溶酶原激活剂的抑制物(PAI-1)活性的影响.方法选择1周内加重的不稳定性心绞痛患者16例,随机分为试验组(n=8)和对照组(n=8).试验组先予乙酰水杨酸水溶片(巴米尔)0.3g口服及依诺肝素钠(克赛)30mg静脉注射+1mg/kg皮下注射,1小时后再予尿激酶50万IU静脉滴注60分.对照组入院即予尿激酶50万IU静脉滴注60分,溶栓前不给予低分子肝素,仅给予肠溶阿司匹林50mg口服.两组分别于溶栓前及溶栓开始后2、4、12、24小时各采静脉血检测FPA、TXB2浓度和t-PA、PAI-1活性.结果①试验组溶栓前后FPA浓度无显著差异;两组间比较FPA浓度在治疗前无差异,溶栓后2小时在对照组出现FPA浓度反弹性增高,有非常显著差异(P＜0.01),同期相比试验组浓度明显低于对照组,有显著差异(P＜0.05).②试验组溶栓后4小时TXB2浓度明显下降;对照组溶栓前后TXB2浓度无显著差异.两组间比较,溶栓后2～12小时试验组TXB2浓度明显低于对照组(P＜0.05).③两组间各时间段PAI-1和t-PA活性的变化比较无明显差异,溶栓后2小时与治疗前比较,PAI-1活性明显降低而t-PA活性明显升高,有非常显著差异(P＜0.001).结论小剂量尿激酶溶栓能明显激活纤溶活性,不增加血小板聚集性,溶栓前未充分抗凝仍会引起凝血酶的激活,但可被预先充分抗凝血酶治疗所抑制,可能有利于减少不稳定性心绞痛患者溶栓后心脏事件的发生.     

番茄红素对实验性高甘油三酯血症大鼠血脂、血凝及纤溶的影响

目的研究番茄红素对实验性高甘油三酯血症大鼠血脂、血凝及纤溶的影响。方法建立大鼠高甘油三酯血症模型,同时给予番茄红素,测定大鼠空腹12~14 h血浆总胆固醇、甘油三酯、高密度脂蛋白胆固醇、凝血酶原时间、活化部分凝血活酶时间、组织型纤溶酶原激活物活性及纤溶酶原激活物抑制剂1活性,分析番茄红素对血脂、血凝及纤溶的影响。结果饲高糖高脂饲料后,大鼠血浆甘油三酯含量平均升高1.95倍,高密度脂蛋白胆固醇下降26%;与高糖高脂饲料组比较,饲高糖高脂饲料及番茄红素后大鼠血浆甘油三酯含量平均下降24%,高密度脂蛋白胆固醇含量平均增加32%,达正常水平。饲高糖高脂饲料后,大鼠血浆凝血酶原时间及活化部分凝血活酶时间均较对照组明显缩短(P<0.01),纤溶酶原激活物抑制剂1活性明显增加(P<0.01),组织型纤溶酶原激活物活性无显著变化。饲高糖高脂饲料及番茄红素后,大鼠血浆纤溶酶原激活物抑制剂1活性明显增加(P<0.01),组织型纤溶酶原激活物活性增加(P<0.01),凝血酶原时间及活化部分凝血活酶时间无明显变化。与高糖高脂饲料组比较,饲高糖高脂饲料及番茄红素后,大鼠血浆凝血酶原时间及活化部分凝血活酶时间均明显延长(P<0.01),纤溶酶原激活物抑制剂1活性明显降低(P<0.05),组织型纤溶酶原激活物活性增加(P<0.01)。结论番茄红素能降低血脂水平,使凝血系统活性降低,纤溶系统活性增加。     

永久心脏起搏术后GPⅡb/Ⅲa、tPA、PAI-1的变化

目的:探讨永久心脏起搏术后对血小板膜糖蛋白Ⅱb/Ⅲa(GPⅡb/Ⅲa),纤溶酶原激活剂(tPA),纤溶酶原激活剂抑制剂-1(PAI-1)的影响。方法:对41例置入永久心脏起搏器患者,测定其术前当天、术后1、7 d 的GPⅡb/Ⅲa、tPA、PAI-1。结果:血小板GPⅡb/Ⅲa在术后1 d及术后7 d均较术前明显降低(P<0．05)。 tPA与术前比较差异无统计学意义(P>0．05),PAI-1术后7 d较术前升高(P<0．05)。结论:心脏起搏降低了血小板活性,升高了PAI-1水平,提示纤溶系统的失衡可能与心脏起搏患者静脉血栓的形成有关。     

Assessment of coagulation and platelet activation in coronary sinus blood induced by transcatheter coronary intervention for narrowing of the left anterior descending coronary artery

Influences of recently developed methods for coronary intervention on hemostasis in the coronary circulation are unclear. The objective of this study was to investigate changes in coagulation and platelet activation in the coronary circulation induced by percutaneous transluminal coronary angioplasty (PTCA). We studied 35 patients with coronary heart disease who underwent elective PTCA to isolated stenotic narrowing of left coronary arteries. Seven patients received only PTCA, 12 underwent percutaneous transluminal rotational atherectomy (PTRA), and 16 underwent stent implantation. Blood samples were drawn from the coronary sinus immediately before and after as well as 4 and 24 hours after PTCA. Plasma levels of tissue factor (TF), thrombin-antithrombin III complex, plasminogen activator inhibitor (PAI)-1, tissue plasminogen activator (t-PA), beta-thromboglobulin, and platelet factor 4 were measured by enzyme-linked immunosorbent assay. In all patients, TF levels in the coronary sinus blood showed significant increases 4 and 24 hours after PTCA and thrombin-antithrombin III complex levels showed significant increases 24 hours after PTCA. PAI-1 showed significant increases 24 hours after PTCA and t-PA showed significant increases 4 and 24 hours after PTCA. Changes in levels of these markers by PTCA were similar among the 3 groups. In PTRA, levels of beta-thromboglobulin and platelet factor 4, markers of platelet activation, increased immediately after the procedure and returned to baseline levels after 4 hours. PTCA induced increases in blood coagulation and fibrinolysis in the coronary circulation. PTRA caused a marked but transient activation of platelets. These changes may contribute to acute complications during the procedure.     

长球囊血管成形术对糖尿病足凝血及纤溶功能的影响

目的：观察长球囊血管成形术治疗糖尿病足术后凝血和纤溶系统活性的动态变化，探讨长球囊血管成形术预防再狭窄的可能机制。方法：选取糖尿病足患者40例，实验组20例，行长球囊血管成形术，对照组20例行短球囊血管成形术，术前，术后即刻、术后24h采取股静脉血，检测组织型纤溶酶原激活物（t—PA）、纤溶酶原激活物抑制剂（PAI-1）、纤维蛋白肽A（FPA）的含量。结果：两组患者的t—PA含量在术后即刻均降低，术后24h实验组的较术后即刻有明显恢复（P〈0．05），且较对照组的显著（P〈0．05），两组分别为（33．30±3．20）ng／ml，（31．01±0．89）ng／ml。PAI-1含量术后两组均显著升高（P〈0．05），24h两组患者均显著降低，实验组降低更显著（P〈0．05），两组分别为（44．33±0．75）ng／ml，（47．86±2．52）ng／ml。FPA含量术后两组均显著升高（P〈0．05），24h两组均显著降低，实验组降低更显著（P〈0．05）。结论：手术前、后t—PA、PAI-1、FPA含量的变化．提示长球囊血管成形术对糖尿病足治疗有效，可能降低血栓事件发生，预防术后再狭窄。     

Prevention of coronary arterial renarrowing by continuous 3-day infusion of tissue plasminogen activator after successful percutaneous transluminal coronary angioplasty: a randomized, double-blind, placebo-controlled study

Vascular injury resulting from percutaneous transluminal coronary angioplasty (PTCA) and subsequent thrombus formation are important factors in the pathogenesis of coronary arterial restenosis. The present study was undertaken to determine whether infusions of tissue plasminogen activator (tPA), beginning immediately after PTCA, would decrease the renarrowing of the coronary arterial lumen. Patients were randomized and divided into two groups: one group (15 patients, 16 lesions) received continuous, 3-day, intravenous infusions of tPA (0.25 mg/kg/day in 0.9% saline), beginning immediately after successful PTCA, while the other group (17 patients, 17 lesions) received saline alone. Coronary angiography was performed before, immediately after, 24 hours after, and 3 months after PTCA. Coronary stenosis (%), reference diameters, and minimum luminal diameters were measured by quantitative coronary angiography. The incidence of restenosis tended to be lower in the tPA group than in the placebo group (tPA group, 13%; placebo group, 41%; NS), although diameter stenoses before and immediately after PTCA were not significantly different in the two groups. Three months later, however, diameter stenoses were significantly smaller in the tPA group (35.6 +/- 13.3 vs 47.7 +/- 18.9%; P<0.05). Thus, intravenous tPA infusion beginning immediately after successful PTCA may inhibit renarrowing of the coronary arterial lumen.     

Hemostatic and fibrinolytic activation is less following cutting balloon angioplasty of the coronary arteries

Recent studies have shown that percutaneous coronary intervention (PCI) activates systemic hemostatic activity, reflecting platelet activation and thrombin formation in the coronary arteries. The present study compared systemic levels of hemostatic markers induced by plain old balloon angioplasty (POBA), coronary stenting (STENT), and cutting balloon (CB) angioplasty. Sixty-one patients with stable angina pectoris, who underwent elective PCI or diagnostic coronary angiography (CAG) alone, were investigated. Patients who underwent PCI were divided into the POBA group (n = 11), the STENT group (n = 27), and the CB group (n = 11). Patients who underwent CAG alone were assigned to the CAG group (n = 12). Blood samples were collected before, 24 hours after, and 3 days after PCI or CAG. Plasma concentrations of prothrombin fragment 1+2 (F1+2), fibrinopeptide A (FPA), thrombin-antithrombin III complex (TAT), and plasminogen activator inhibitor-1 (PAI-1) were measured. In the CB group, the F1+2 (1.23 +/- 0.4 nmol/L) level 3 days after PCI was significantly smaller than that of the POBA group (2.37 +/- 0.5 nmol/L) (P < 0.05). The FPA (1.81 +/- 0.9 ng/mL), TAT (3.36 +/- 1.2 ng/mL) and PAI-1 (23.0 +/- 4.1 ng/mL) levels in the CB group 3 days after PCI were significantly smaller than those of the POBA group (P < 0.05, respectively) and STENT group (P < 0.05, respectively), but similar to the CAG group. Systemic hemostasis is activated to a greater extent after POBA and stenting than it is after CB angioplasty of the coronary arteries. This may contribute to the favorable long-term outcome of CB angioplasty.     

持续气道正压通气对OSAHS患者血管内皮细胞及纤溶系统的影响

为探讨经鼻持续气道正压通气（nCPAP)治疗前后阻塞性睡眠呼吸暂停低通气综合征（OSAHS）患者血管内皮细胞及纤溶系统的变化及临床意义，选择年龄，性别，体重指数（BMI）无明显差异的OSAHS患者38例和健康者对照组32例，用多导睡眠呼吸监测仪进行监测，以凝固法测定纤维蛋白原（Fg），发色底物法测组织纤溶酶原激活物活性（tPA：A）、纤溶酶原激活物抑制物－1活性（PAI－1：A），酶联免疫法测vonWillebrand因子（vWF)、组织纤溶酶原激活物抗原（tPA:Ag）、纤溶酶原含量（PLg:Ag)和纤溶酶原激活物抑制物－1含量（PAI－1：Ag）。结果OSAHS组与对照组比较，vWF,Fg,tPA:Ag、PAI－1：A明显升高（P分别＜0．01，0．001，0．001，0．01），PLg:Ag、tPA:A、tPA:Ag、最低血氧饱和度（SaO2low)明显降低（P分别＜0．01，0．001，0．001，0．01).nCPAP治疗后与治疗前比较，vWF,Fg,PAI-1:Ag,PAI-1:A明显降低（P分别＜0．05，0．01，0．01，0．01），PLg:Ag,tPA:A,tPA:Ag，最低SaO2明显升高（P分别＜0．05，0．001，0．001，0．01）。提示OSAHS患者血管内皮细胞损伤，凝血功能增强，纤溶系统功能减弱;nCPAP治疗能部分纠正各指标的异常。     

Plasma levels of plasminogen activator inhibitor type 1, beta- thromboglobulin, and fibrinopeptide A before, during, and after treatment of acute myocardial infarction with alteplase

Plasma levels of plasminogen activator inhibitor type-1 (PAI-1), beta- thromboglobulin (beta TG), and fibrinopeptide A (FPA) were followed over 24 hours in 30 patients treated with alteplase for acute myocardial infarction. Samples were taken at baseline (T Oh), after 90 minutes (under alteplase, no heparin, T 1.5h), after 120 minutes (under alteplase and heparin, T 2h), 30 minutes after thrombolytic therapy (T 3.5h), as well as 12 hours (T 12h) and 24 hours (T 24h) after baseline. PAI-1 antigen levels (55 +/- 9 ng/mL at T Oh, mean +/- SEM) decreased to 35 +/- 5 (T 1.5h) and 40 +/- 6 (T 2h) ng/mL under alteplase, before increasing to 84 +/- 22 (T 3.5h), 130 +/- 30 (T 12h), and 64 +/- 7 (T 24h) ng/mL after therapy, P less than .001. A high baseline PAI-1 activity (18 +/- 3 ng/mL) decreased to 2.0 +/- 0.4 (T 1.5h) and 1.7 +/- 0.2 (T 2h) under alteplase and increased to 32 +/- 5 (T 12h) and 19 +/- 3 (T 24h) ng/mL after therapy (P less than .0001). beta TG levels (339 +/- 105 ng/mL at T Oh) decreased to 203 +/- 48 (T 2h), 154 +/- 51 (T 3.5h), 187 +/- 40 (T 12h), and 142 +/- 32 (T 24h) ng/mL under heparin (P less than .01). FPA levels (34 +/- 9 ng/mL at T Oh) increased to 85 +/- 15 ng/mL under alteplase alone (T 1.5h) and normalized under heparin (11 +/- 4, 6 +/- 2, 4 +/- 2, and 3 +/- 1 ng/mL at T 2h, T 3.5h, T 12h, and T 24h, respectively). A high level of FPA at T 3.5h correlated with reocclusion (33 +/- 12 ng/mL, n = 4 v 2.9 +/- 0.5 ng/mL, n = 21, P less than .005). We conclude that plasma levels of PAI- 1 antigen as well as activity markedly increase after alteplase therapy of acute myocardial infarction. The high activity of PAI-1 and decreasing beta TG levels suggest that platelets do not contribute significantly to this phenomenon. The marked increase of FPA levels under recombinant tissue-type plasminogen activator alone and its normalization under heparin emphasize the important role of concomitant anticoagulation in controlling further intravasal fibrin generation under alteplase.     

疏血通注射液对心房颤动患者血栓前状态的影响

目的研究疏血通注射液对心房颤动患者血栓前状态的改善作用。方法将63例心房颤动患者随机分为疏血通组和对照组,疏血通组应用疏血通注射液治疗14d,对照组除不使用疏血通,其他用药与疏血通组相同。治疗前和治疗2周后测量两组血浆纤溶酶原激活物(tPA)及其抑制物(PAI-1)活性,D-二聚体(D-D)和血管性假血友病因子(vWF)水平。结果疏血通组和对照组在治疗前血浆tPA、PAI-1活性、D-D和vWF水平无统计学意义(P>0.05)。疏血通组治疗后血浆tPA活性显著性增高(P<0.05),血浆PAI-1活性、D-D和vWF水平均显著性下降(P<0.05),而对照组无显著性改变(P>0.05)。组间比较发现,疏血通组治疗后血浆PAI-1活性、D-D和vWF水平比对照组更低(P<0.05),而血浆tPA活性无显著增高(P>0.05)。结论短期疏血通静脉输注可以明显改善心房颤动患者的血栓前状态,这可能降低心房颤动患者的血栓栓塞危险。     

Transcriptional profiling after bile duct ligation identifies PAI-1 as a contributor to cholestatic injury in mice

Extrahepatic cholestasis leads to complex injury and repair processes that result in bile infarct formation, neutrophil infiltration, cholangiocyte and hepatocyte proliferation, extracellular matrix remodeling, and fibrosis. To identify early molecular mechanisms of injury and repair after bile duct obstruction, microarray analysis was performed on liver tissue 24 hours after bile duct ligation (BDL) or sham surgery. The most upregulated gene identified encodes plasminogen activator inhibitor 1 (PAI-1, Serpine 1), a protease inhibitor that blocks urokinase plasminogen activator (uPA) and tissue-type plasminogen activator (tPA) activity. Because PAI-1, uPA, and tPA influence growth factor and cytokine processing as well as extracellular matrix remodeling, we evaluated the role of PAI-1 in cholestatic liver injury by comparing the injury and repair processes in wild-type (WT) and PAI-1-deficient (PAI-1-/-) mice after BDL. PAI-1-/- mice had fewer and smaller bile infarcts, less neutrophil infiltration, and higher levels of cholangiocyte and hepatocyte proliferation than WT animals after BDL. Furthermore, PAI-1-/- mice had higher levels of tPA activation and mature hepatocyte growth factor (HGF) after BDL than WT mice, suggesting that PAI-1 effects on HGF activation critically influence cholestatic liver injury. This was further supported by elevated levels of c-Met and Akt phosphorylation in PAI-1-/- mice after BDL. In conclusion, PAI-1 deficiency reduces liver injury after BDL in mice. These data suggest that inhibiting PAI-1 might attenuate liver injury in cholestatic liver diseases.     

Plasmin Activation System in Restenosis: Role in Pathogenesis and Clinical Prediction?

During recent years it has become increasingly recognized that the plasmin activation system is involved in the development of atherosclerosis and restenosis. Responsible pathophysiologic mechanisms, however, remain elusive. This review focuses primarily on the clinicians, point of view, suggesting that increases in plasminogen activator inhibitor type-1 (PAI-1) plasma levels after balloon angioplasty or permanently elevated lipoprotein (a) (Lp(a)) plasma levels might be helpful in the prediction of restenosis after coronary angioplasty. In contrast, tissue-type plasminogen activator (tPA) plasma levels appear unrelated to restenosis, and data regarding a possible role of urokinase-type plasminogen activator (uPA) in circulation are not available at present. Furthermore, a new hypothesis on the pathophysiological role of local PAI-1 overexpression as a beneficial negative feedback mechanism to limit excess cellular proliferation in atherogenesis and restenosis is presented.     

Hypo-fibrinolysis in patients with hypertension and elevated cholesterol

To test the hypothesis that increased blood pressure and hyperlipidaemia result in changes in the fibrinolytic system, 84 subjects with both hypertension and elevated serum cholesterol levels (the high risk group) were compared with 55 controls matched with respect to age, sex and body mass index (BMI). Plasminogen activator inhibitor (PAI-1), and tissue plasminogen activator (tPA) antigen and activity were measured before and after venous occlusion. In the high risk group, tPA activity was significantly lower both before and after venous occlusion and PAI-1 levels were significantly higher. In a multivariate analysis the triglyceride levels, diastolic blood pressure and cholesterol levels were independently associated with the PAI-1 levels. Diastolic blood pressure was independently and inversely associated with resting tPA activity. We conclude that patients with hypertension and hyperlipidaemia have a reduced activity of the fibrinolytic system, an effect which is unrelated to differences in age, sex, smoking or BMI.