NIDDM伴微量白蛋白尿患者纤溶异常的初步观察

测定12例NIDDM伴MAU患者血浆D-二聚体（D-D）、组织型纤溶酶原激活物（t-PA）及其抑制物（PAI-1）活性，并与12例不伴MAU的患者及12例正常人进行比较。发现MAU患者血浆D-D升高，t-PA活性降低，PAI-1活性上升。以上指标与24小时尿白蛋白排泄（UAE）、胰岛素抵抗（IR）及血脂呈不同程度的相关性。表明NIDDM伴MAU患者存在高凝低纤溶状态，其发生可能与血管内皮损伤、胰岛素抵抗及脂质代谢紊乱有关。     

全蝎纯化液对凝血酶诱导血管内皮细胞纤溶活性的影响

目的观察不同浓度全蝎纯化液对凝血酶诱导血管内皮细胞(VEC)释放组织型纤溶酶原激活物(t-PA)、纤溶酶原激活物抑制物(PAI)活性的影响。方法以凝血酶和不同剂量的全蝎纯化液同时作用于培养的人脐静脉内皮细胞(VEC-340),12h后收集细胞液测定t-PA和PAI活性。结果与空白组比较,凝血酶组t-PA活性降低,PAI活性增高,差异有统计学意义(P0.01),与凝血酶组比较,全蝎大剂量、中剂量、小剂量组t-PA活性均增高,PAI活性降低,差异均有统计学意义(P0.01)。结论凝血酶对VEC-340细胞具有损伤作用,可诱导内皮细胞抗血栓性发生变化。全蝎纯化液可促进血管内皮细胞释放t-PA,抑制PAI分泌,对纤溶平衡具有调节作用。提示这可能与全蝎纯化液增加血管内皮细胞抗血栓能力有关。     

2型糖尿病纤溶系统变化与胰岛素抵抗的关系

目的探讨2型糖尿病患者纤溶活性变化与胰岛素抵抗之间的关系。方法采用酶联免疫吸附法测定63例2型糖尿病患者（包括无血管并发症组30例和有血管并发症组33例）和25例正常对照者血浆组织型纤溶酶原激活剂（t-PA）、纤溶酶原激活物抑制剂-1（PAI-1）含量,结合临床资料分析其变化趋势及影响因素。结果2型糖尿病患者血浆t-PA含量明显降低（P〈0．01）,而PAI-1含量明显升高（P〈0．01）,合并血管病变者,此变化更为显著（均P〈0．001）。多元逐步回归分析显示,HOMA模型胰岛素抵抗指数（HOMA—IR）是PAI-1升高的独立危险因素。结论2型糖尿病患者纤溶活性降低,胰岛素抵抗在降低其纤溶活性,并发血管病变中起了重要作用。     

老年高血压病患者早期肾损害中组织型纤溶酶原激活物和纤溶酶原激活物抑制剂的作用

为研究老年高血压病患者纤溶活性异常与肾脏损害的关系 ,选择 5 2例血清肌酐正常的老年原发性高血压患者和 2 2例血压正常的老年人 ,用发色底物法测定血浆组织型纤溶酶原激活物和纤溶酶原激活物抑制剂活性 ,用酶联免疫吸附法测定尿微量转铁蛋白和视黄醇结合蛋白含量 ,并进行相关分析。结果发现 ,老年高血压病患者与正常血压者比较 ,血浆组织型纤溶酶原激活物活性显著下降 ,血浆纤溶酶原激活物抑制剂活性和尿微量转铁蛋白、视黄醇结合蛋白含量显著升高 ;血浆组织型纤溶酶原激活物活性与尿转铁蛋白 (r =- 0 .792 8)、视黄醇结合蛋白 (r=- 0 .85 2 2 )含量呈显著负相关 (P <0 .0 0 0 1) ,而血浆纤溶酶原激活物抑制剂活性与尿转铁蛋白 (r =0 .7497)、视黄醇结合蛋白 (r=0 .82 69)含量呈显著正相关 (P <0 .0 0 0 1) ,提示老年高血压病患者存在的纤溶活性异常可能在其肾脏损害进程中起重要作用     

马来酸罗格列酮对大鼠血浆tPA和PAI-1活性的影响

STZ诱导的糖尿病大鼠研究显示，罗格列酮治疗（每日4mg／kg，3周）能增加组织型纤溶酶原激活物（tPA）的血浆水平，降低PAI—1的活性，降低PAI-1／tPA的比值。因此，罗格列酮可能有心血管保护作用。     

肝硬化患者纤溶活性变化与t-PA、PAI的关系

目的探讨肝硬化患者纤溶活性增高与组织纤溶酶原激活物(t-PA)、组织纤溶酶原激活物抑制剂(PAI)的关系.方法根据Child-Pugh分级将确诊为肝硬化的86例患者分为三组,A级组26例,B级组30例,C级组30例.均检测t-PA、PAI、纤维蛋白(原)降解产物(FDP)和D-二聚体.结果三组t-PA抗原随病情严重程度而显著性升高,有显著性差异(P＜0.05);PAI活性三组近似(P＞0.05);纤溶活性高者的t-PA略高于正常纤溶者,且二者PAI近似,均无显著性差异(P＞0.05).结论 t-PA随病情加重而显著性升高,PAI随病情加重变化不大;t-PA、PAI失平衡不是肝硬化患者纤溶活性升高的主要因素.     

血浆纤溶与胰岛素抵抗综合征

血浆纤溶受损在动脉粥样硬化及心血管病的进展中发挥了重要作用，而胰岛素抵抗（IR）是心血管病的重要危险因素，近年研究显示，肥胖、高血压、高胰岛素血症等胰岛素抵抗综合征（IRS）与血浆纤溶酶原激活物抑制物1（PAI－1）活性的增高密切相关，细胞因子失调可能是其联系所在。     

2型糖尿病患者血浆t-PA、PAI-1水平与颈动脉粥样硬化关系

探讨2型糖尿病患者血浆纤溶活性因子组织型纤溶酶原激活物(t-PA)、纤溶酶原激活物抑制物-1(PAI-1)水平与颈动脉粥样硬化(carotid atherosclerosis,CAS)的关系.将91例2型糖尿病患者根据颈动脉超声内膜中层厚度分为4组并设健康对照组,分析CAS程度与血浆t-PA、PAI-1水平的关系.结果显示CAS程度与t-PA水平呈明显负相关(r=-0.723,P＜0.01),与PAI-1水平均呈明显正相关(r=0.851,P＜0.01).提示2型糖尿病患者纤溶功能异常可能参与了大血管粥样硬化的发生、发展过程.     

动脉粥样硬化与血浆组织型纤溶酶原激活物及其抑制剂活性的相关性

组织型纤溶酶原激活物（tPA）与纤溶酶原激活物抑制剂（PAI）的活性与血液纤溶系统密切相关。两者保持着动态平衡，一旦平衡失调，可导致血栓形成或出血。国内外许多研究发现，急性心肌梗死和急性脑梗死患者血浆tPA活性下降，而PAI活性升高，这为临床应用tPA溶栓治疗急性心肌梗死和急性脑梗死提供了理论依据。动脉粥样硬化是心肌梗死及脑梗死的重要危险因素，动脉粥样硬化软斑表面存在血栓附着，那么动脉粥样硬化期是否也存在tPA、PAI活性的异常？作者对此进行了研究。     

老年高血压病患者性激素与血管内皮功能的关系

为研究老年高血压病患者性激素,vWF含量和纤溶活性的改变及其相关性,分别采用放射免疫法,酶联免疫吸附法和发色底物法测定了66例（女34例,男32例）I,II期老年高血压病患者和32例（女16例,男16例）老年正常人的雌二醇,睾酮及内皮损伤特异性标志物－von Willebrand因子含量,以及组织型纤溶酶原激活物和纤溶酶原激活物抑制物活性,并进行了相关性分析,结果发现,老年女性高血压病雌二醇水平,组织型纤溶酶原激活物活性明显低于老年女性正常对照组（P＜0．01,P＜0．05）,而von Willebrand因子含量,纤溶酶原激活物抑制物活性明显高于正常对照组（P＜0．05,P＜0．01）,老年男性高血压病组睾酮水平,组织型纤溶酶原激活物活性明显低于老年男性正常对照组（P＜0．05,P＜0．01）,von Willebrand因子含量,纤溶酶原激活物抑制物活性显著高于正常对照组（P＜0．05,P＜0．01）,老年女性高血压病组雌二醇水平与von Willebrand因子含量呈显著负相, 结果提示,老年女性高血压病患者雌二醇水平明显降低,而男性睾酮水平下降,两者都存在明显的内皮损伤,纤溶活性异常,雌二醇可能通过对血管内皮功能的有利影响而对女性高血压起保护作用。     

Determination of plasma tissue type plasminogen activator and plasminogen activator inhibitor activity in patients with ischemic stroke

Plasma tissue-type plasminogen activator and plasminogen activator inhibitor were determined during the acute, recovery and sequelae stages of patients with ischemic stroke by chromophoric substrate assay. The result showed that t-PA activity was elevated during the acute phase, remained elevated during the recovery stage and declined during the sequelae stage. Lowering of PAI activity was found during acute phase, which reversed during recovery phase and remained significantly elevated during sequelae stage. As a result, the ratio of PAI/t-PA fluctuated during different stages of the disease. Significant elevation of PAI and PAI/t-PA ratio during sequelae stage may be one of the risk factors of further thrombosis and contribute partly to the high relapsing rate of the disease. In addition, a positive correlation was found between PAI and serum cholesterol content.     

Sex-related differences in plasminogen activator activity and plasminogen activator inhibition of human and animal kidneys: effect of orchidectomy or ovariectomy.

Plasminogen activator activity (PAA), plasminogen activator inhibition (PAI) and plasmin inhibition (PI) have been studied with spectrophotometric methods in extracts of human, bovine, ovine and rat kidneys of both sexes. In all species studied, renal PAA (cortex or medulla) was higher in females than in males. The PAA was also higher in the medulla than in the cortex in all species and both sexes. The PAA was due to both types of plasminogen activator; tissue-type plasminogen activator (t-PA) and urokinase-type plasminogen activator (u-PA). In the human kidney (cortex or medulla) the measurement of t-PA antigen showed that t-PA is higher in females than in males; t-PA is also higher in the medulla than in the cortex in both sexes. The PAI showed the opposite pattern in all species studied; it was lower in females than in males. It was also lower in the medulla than in the cortex. PAI-1 was identified in the human kidney. Sex-related differences in renal PAA or PAI almost disappeared after bilateral orchidectomy in rats. PI showed no sex or regional differences in the species studied. Sex-related differences in renal PAA and PAI in man and various animal species might be of physiological or pathophysiological importance.     

Time dependent release of tissue-type plasminogen activator and plasminogen activator inhibitor into the circulation of pigs during shock.

To investigate short-term activation and inhibition of fibrinolysis during shock, we studied plasma levels of tissue-type plasminogen activator (t-PA) and t-PA inhibition capacity (PAI) in anaesthetized pigs. t-PA in euglobulin fractions of plasma was measured by the conversion of plasminogen to plasmin in the presence of fibrin split products. Plasmin thus generated was measured in a chromogenic substrate assay. PAI was measured as plasma inhibition capacity for human melanoma t-PA. Controls (n = 8) had constant t-PA and PAI for 6 h. Lipopolysaccharide from Salmonella abortus equi in four different doses (n = 9 - 11), or live Escherichia coli (n = 3) induced a transient t-PA increase with peak values at 2 h. PAI decreased to 50% at 2 h and increased to 250% at 6 h. Phorbol myristate acetate (n = 7) induced no change of t-PA or PAI. Dextran sulphate (n = 4) produced a t-PA rise at 30 min, followed by a rapid decline. Endotoxin was an appropriate stimulus for activation and inhibition of fibrinolysis whereas phorbol ester failed to elicit this response.     

Inhibition of tissue plasminogen activator activity by aspirin in vivo and its relationship to levels of tissue plasminogen activator inhibitor antigen, plasminogen activator and their complexes

The observation that aspirin inhibits the increment in tissue plasminogen activator (t-PA) activity induced by venous occlusion of the forearm became controversial with the publication of several nonconfirmatory studies. The current study was performed to confirm the original observation and determine the mechanism by which aspirin suppresses the incremental t-PA activity induced by venous occlusion. Aspirin (650 mg/d X 2) caused no change in resting levels of t-PA antigen (t-PA:Ag) or activity, plasminogen activator inhibitor 1 antigen (PAI-1:Ag), or activity or t-PA-PAI-1 complexes. In contrast, aspirin reduced the increments induced by venous occlusion as follows: t-PA:Ag by 45% (P = .001); t-PA activity (euglobulin lysis time, ELT) by 43% (P = .006); and t-PA activity (alpha 2-plasmin inhibitor-plasmin complexes, PIPC) by 41% (P = .003). The inhibition of incremental t-PA activity measured as ELT or PIPC was linearly correlated with the inhibition of incremental t-PA:Ag (respectively, r = .75, P less than .02; r = .67, P less than .05). Aspirin had no effect on the increment in PAI-1:Ag induced by venous occlusion, but similar to the effect on t- PA:Ag, aspirin induced a 51% inhibition of the increment in t-PA-PAI-1 complex formation. Aspirin did not alter the ability of alpha 2-plasmin inhibitor to bind plasmin, nor the ability of plasma to support the fibrin-catalyzed generation of plasmin by t-PA, nor the subsequent formation of PIPC. Aspirin inhibits the t-PA activity induced by venous occlusion primarily by inhibiting the release of t-PA antigen.     

Tissue plasminogen activator, plasminogen activator inhibitor, and other parameters of fibrinolysis in the early stages of taurocholate acute pancreatitis in rats.

It is well known that fibrinolytic activity in the early stages of acute experimental pancreatitis (AEP) as assessed by euglobulin lysis time (ELT) is depressed. The aim of this study was to evaluate changes in the fibrinolytic system in the early stages of taurocholate AEP in rats. Tissue plasminogen activator (t-PA) activity, plasminogen activator inhibitor 1 (PAI-1) activity, plasminogen, alpha 1 proteinase inhibitor (alpha 1 PI), alpha 2 antiplasmin (alpha 2 AP), antithrombin III (AT III), fibrinogen, and ELT were measured 0.5, 1, 3, and 6 h after the induction of taurocholate AEP in rats, as well as in sham-operated animals and the control group, which was not submitted to any operation. T-PA activity decreased significantly after 3 and 6 h of AEP; PAI activity had a time course reverse to t-PA and was parallel to alpha 1 PI activity. ELT was slightly prolonged after 0.5, 1, and 3 h, whereas alpha 2 AP activity and plasminogen levels increased significantly; AT III activity was increased after 1 h in comparison to control group. Sham operation caused nonsignificant changes in fibrinolysis. Increase of PAI activity and decrease of t-PA could be a reasonable explanation for inhibited plasma euglobulin fibrinolytic activity noted in the early period of AEP.     

A moderate fish intake increases plasminogen activator inhibitor type-1 in human volunteers

For a period of 6 weeks, 76 healthy male volunteers consumed during their daily main meal the contents of one tin (approximately 135 g) of either fish (mackerel) paste or meat paste. Fibrinolytic parameters were determined in plasma samples obtained at the beginning and at the end of the experimental period. No changes were found in plasminogen, alpha 2-antiplasmin, tissue-type plasminogen activator (t-PA) antigen, and euglobulin t-PA activity. In the control group (n = 39), plasminogen activator inhibitor activity did not change. In the fish group (n = 37), however, total plasma PA inhibitor (PAI) activity increased by 45%, due to a 71% increase in PA inhibitor type-1. This increase could not be ascribed to a diet-induced acute phase-type reaction and could not be explained by changes in serum triglycerides or insulin.     

Evidence for increased levels of plasminogen activator inhibitor and tissue plasminogen activator in plasma of patients with angiographically verified coronary artery disease

We studied 234 consecutive patients who underwent coronary angiography because of severe angina pectoris. Tissue plasminogen activator (tPA), plasminogen activator inhibitor (PAI), and lipoprotein Lp(a) were measured in citrated plasma samples. The 214 patients showing significant coronary artery stenosis (greater than 50% reduction of luminal area in any of the great coronary arteries) had higher mean levels of tPA (P less than 0.001) and PAI (P less than 0.01) than a random population sample of similar age. PAI and tPA levels were higher in smokers than in either non-smokers or ex-smokers, and in patients with hypertension tPA was increased. Subjects with blood group A had a higher mean Lp(a) level than subjects with blood group O. There were positive correlations of PAI and tPA levels with serum triglycerides and with body mass index; Lp(a) correlated weakly with plasma fibrinogen concentrations. The findings suggest an impairment of the fibrinolytic system in patients with coronary artery disease, which offers a link between established risk factors and a plausible pathophysiological mechanism, namely thrombus turnover.     

Tissue plasminogen activator levels in different types of polycythemia

The plasma level of tissue plasminogen activator antigen (t-PA-Ag) was examined in 86 patients with polycythemia (29 polycythemia vera, 11 secondary polycythemia and 46 with spurious polycythemia) and 24 healthy volunteers. Tissue plasminogen activator antigen was significantly decreased in patients with polycythemia vera in comparison with healthy controls. On the other hand, in patients with spurious polycythemia and secondary polycythemia t-PA-Ag concentration was significantly increased. There was no significant difference in t-PA-Ag levels in polycythemic patients with or without thromboembolic disease. A significant correlation was detected between t-PA-Ag level and hemoglobin or hematocrit concentration in patients with polycythemia vera (p = 0.02, r = 0.43). However, in patients with secondary polycythemia and spurious polycythemia, no significant correlation between t-PA-Ag and hemoglobin level was found. Plasminogen activator inhibitor (PAI) levels in patients with polycythemia vera and healthy volunteers did not differ significantly.     

Clinical significance of urokinase-type plasminogen activator activity in hepatocellular carcinoma

BACKGROUND AND METHODS: The plasminogen activation system plays a crucial role in the process of cancer invasion and metastasis. To evaluate the most effective factor in the invasion, metastasis and prognosis of hepatocellular carcinoma (HCC), we examined urokinase-type plasminogen activator (uPA), plasminogen activator inhibitor (PAI)-1, PAI-2 and uPA activity by enzyme-linked immunosorbent assays (ELISA) in HCC tissues obtained from 46 patients. The results were compared with the patients' clinicopathological features and prognoses. RESULTS: Of the clinicopathological features, only histological portal involvement or intrahepatic metastasis, or both (INV), was significantly correlated to the disease-free survival rates (DFS; P < 0.05). The levels of uPA, PAI-1 and PAI-2 antigens were significantly associated with INV and histological grade. The DFS was not different, however, between cases with uPA, PAI-1 and PAI-2 values above and below the median. The high levels of uPA activity were closely related to INV (P < 0.001), and the activity gradually raised histological grades (P < 0.0001). The DFS was significantly different between patients with uPA activity below and above the median (0.70 ng/mL; P = 0.0092); it was also significantly different between such patients without INV (P < 0.05). CONCLUSIONS: Urokinase-type plasminogen activator activity may be the most sensitive factor affecting HCC invasion in the plasminogen activation system and a strong predictor for the recurrence of HCC. We suggest that cases with uPA activity of more than 0.70 ng/mL should be carefully followed up for possible HCC recurrence.     

培哚普利对慢性心力衰竭患者血浆t-PA和PAI-1水平的影响

目的评价培哚普利对慢性心力衰竭(CHF)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测定60例CHF患者(CHF组)及20例健康人(正常对照组)血浆t-PA、PAI-1水平。CHF组患者又随机均分为常规治疗亚组和培哚普利亚组。培哚普利亚组在常规治疗基础上加用培哚普利2~4mg,每日1次。所有CHF患者治疗2周后复测血浆t-PA、PAI-1水平。结果CHF患者血浆t-PA、PAI-1水平比正常对照组明显增高(P<0.01)。治疗后,培哚普利亚组血浆PAI-1水平比常规治疗亚组明显降低(P<0.01),血浆t-PA水平比常规治疗亚组明显升高(P<0.01)。结论培哚普利不仅可降低PAI-1水平,而且可升高t-PA水平,改善内源性纤溶功能。