幼鼠残肾组织凝血酶敏感蛋白-1介导凝血纤溶与肾纤维化的相关研究

目的探讨在幼年性慢性进展性肾脏病不同时间点肾组织凝血酶敏感蛋白(TSP)-1表达对肾组织凝血纤溶系统的影响,及其与肾纤维化的相关性。并探讨血管紧张素转换酶抑制剂(ACEI)的干预作用。方法用5/6肾切除残肾幼年大鼠为模型,分为不治疗组、治疗组、假手术组。于实验开始,4、8、12周为时间点,检测体质量、血压、尿蛋白定量(24h)等。用免疫组织化学法检测TSP-1、血浆凝血酶原激活物抑制物(PAI)-1、转化生长因子(TGF)-β1、尿激酶型纤溶酶原激活物(uPA)、组织型纤溶酶原激活物(tPA)的表达趋势。分析上述指标在病变进展过程中的变化特点及相关性。判断ACEI的干预效果。结果不治疗组残肾组织中tPA和uPA的表达较假手术组减少,PAI-1的表达增加。治疗后大鼠残肾组织中tPA、uPA表达明显增加,PAI-1表达明显减少。5/6肾切除大鼠各组残肾组织中TSP-1和TGF-β1的表达较假手术组上调,且呈同步上调趋势,治疗组TSP-1和TGF-β1表达则明显趋于下调,治疗组残肾组织TSP-1表达在组织定位上与肾小球硬化和肾小管间质纤维化趋势呈正相关,TSP-1表达与TGF-β1和PAI-1表达呈明显正相关,与uPA和tPA表达呈负相关。结论TSP-1和TGF-β1是促进肾纤维化的重要因子,TSP-1高表达通过影响tPA、uPA、PAI-1及其平衡导致肾组织凝血纤溶系统平衡发生紊乱而促进病变发展。     

苯那普利对肾病幼鼠纤溶蛋白肾组织定位表达的影响

目的　探讨肾病幼年大鼠肾小球硬化及肾间质纤维化病变进展过程中 ,肾组织尿激酶型纤溶酶原激活物 (u PA )、组织型纤溶酶原激活物 (t PA)及其特异性抑制物 (PAI- 1)蛋白定位表达的特点 ,及予血管紧张素转换酶抑制剂 (ACEI)——苯那普利 (benazepril;lotensin)治疗的影响。方法　采用阿霉素诱导的肾病大鼠为动物模型 ,予 ACEI治疗 12周后测大鼠体重、血压、尿蛋白、及血生化各项指标的变化 ,同时用免疫组织化学染色等方法检测各组肾组织 u PA、t PA和 PAI- 1的蛋白表达的变化特点。结果　肾病大鼠肾组织 PAI- 1表达均高于正常对照组 ,而 u PA、t PA均低于正常组 ;经治疗后肾组织 PA I- 1趋于下降 ,而 u PA、t PA表达趋于增高 (P<0 .0 1)。结论　纤溶系统的平衡紊乱是肾病大鼠肾小球硬化和肾间质纤维化进展中的重要病生理变化之一 ,ACEI治疗可改善 PAs/ PAI- 1的异常表达 ,防止细胞外基质的异常沉积 ,阻止肾小球硬化和间质纤维化病变进展。     

残肾大鼠血小板反应蛋白表达与肾组织纤溶状态的关系

目的　研究 7/ 8肾切除慢性肾衰大鼠肾小管间质病变过程中血小板反应蛋白 (TSP) 1与尿激酶型纤溶酶原激活物 (uPA)蛋白表达在调节纤溶系统功能中的意义。方法　以 7/ 8肾切除SD大鼠为实验动物模型 ,予水蛭和ACEI 洛汀新治疗 12周后杀检残肾常规病理改变 (PAS染色 )。免疫组织化学染色观察残肾组织TSP 1与uPA蛋白表达变化 ,并比较二者表达的相关性及TSP 1与间质纤维化病变的相关性。结果　 7/ 8肾切除后大鼠残肾出现进行性肾小球硬化及间质纤维化病变 ,临床上表现为慢性肾功能衰竭。给予治疗后肾功能明显改善 ,残肾组织病理改变好转。免疫组化提示肾小管间质区TSP 1、uPA蛋白表达上调 ,且二者表达在时相和定位上呈正相关 ,而TSP 1表达与间质纤维化程度则呈负相关。结论　本研究提示在慢性肾衰大鼠间质病变经治疗恢复过程中uPA与TSP 1的表达具有促纤溶作用     

中药芪红合剂对肾间质纤维化模型大鼠肾组织中PAI-1表达的影响

目的:探讨中药芪红合剂对肾问质纤维化模型大鼠肾组织中纤溶酶原激活物抑制剂-1(PAI-1)表达的影响,及其对肾间质纤维化的作用机制.方法:采用单侧输尿管结扎(UUO)致肾问质纤维化的动物模型,40只雄性Wistar大鼠随机分为4组:假手术组(A组)、手术模型组(B组)、芪红合剂组(C组)、依那普利组(D组).术后14 d处死各组大鼠.收集血清、测定血肌酐(Scr)、尿素氮(BUN)水平,取结扎侧肾组织分别用HE、Masson染色,采用免疫组化检测肾组织中纤溶酶原激活物抑制剂-1(PAI-1)的表达,并用计算机图像分析系统进行分析.结果:模型组大鼠肾组织中PAI-1的表达较假手术组显著升高.两治疗组较模型组明显降低.模型组大鼠血肌酐、尿素氮水平较假手术组明显增高、两治疗组较模型组显著下降.结论:中药芪红合剂可降低大鼠血尿素氮、血肌酐水平,并可通过抑制纤溶酶原激活物抑制剂-1(PAI-1)的表达,而起到减轻肾间质纤维化病变程度的作用,推测其抑制PAI-1表达上调的作用可能是其抗肾间质纤维化的作用机制之一.     

Ghrelin对肿瘤坏死因子-α诱导HepG_2细胞纤溶酶原激活物抑制剂-1分泌的干预作用

目的探讨ghrelin对肿瘤坏死因子-α(TNF-α)诱导的HepG2细胞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)分泌的影响。方法HepG2细胞培养,加入不同浓度和时间TNF-α,采用酶联免疫吸附试验法测定细胞上清、PAI-1、tPA含量,采用ghrelin预处理1h后,加TNF-α检测二者变化。结果TNF-α(0.1、1、10μg/L)浓度、时间(2、6、24h)依赖地增高PAI-1,tPA轻度增加,tPA/PAI-1下降;ghrelin抑制单独作用和TNF-α诱导的PAI-1分泌,增加tPA,提高tPA/PAI-1。结论Ghrelin可抑制基础的和TNF-α诱导的PAI-1分泌。     

替米沙坦与非洛地平对原发性高血压纤溶系统的影响

目的 比较替米沙坦和非洛地平对原发性高血压患者纤溶系统的影响.方法 60例原发性高血压患者随机均分为替米沙坦组和非洛地平组,观察治疗后血压、血浆组织型纤溶酶原激活物(tPA)及其抑制物(PAI-1)含量、D-二聚体(D-D)和血管性血友病因子(vWF)水平的变化.结果 两组患者治疗后血压均显著下降(P<0.01),PAI-1、vWF和D-D水平均显著性下降(P<0.05),tPA和tPA/PAI-1比值明显升高(P<0.05).组间D-D和vWF水平无显著差异,替米沙坦组PAI-1含量减少更明显、tPA和tPA/PAI-1比值增加更显著.结论 替米沙坦和非洛地平缓释片均能有效改善原发性高血压的纤溶障碍,但替米沙坦优于非洛地平.     

过敏性紫癜肾儿童血尿纤溶酶原激活物及其抑制物的变化及干预治疗

目的　探讨过敏性紫癜肾患儿外周血和尿液中组织型纤溶酶原激活物 (tPA)及 1型纤溶酶原激活物抑制物 (PAI 1)的活性和尿纤溶酶原激活物总活性 (PAs)的变化特点及予血管紧张素转化酶抑制剂 (ACEI)、低分子肝素治疗的影响。方法　 2 3例紫癜肾儿童为研究对象 ,11名正常对照。分别于ACEI和低分子肝素治疗前、治疗后 1周、治疗后 2周取血、尿标本 ,用纤维平板法测定尿PAs活性 ,用酶联免疫吸附测定 (ELISA)法测定血tPA和PAI 1活性 ,以 x±s报道数据。 结果　紫癜肾患儿于治疗前血tPA水平和尿PAs总活性均明显低于正常对照组 ,而PAI 1水平则显著高于对照组 ,ACEI和肝素联合治疗后 ,随着治疗的持续可明显改善凝血纤溶系统平衡紊乱的趋势 (P <0 0 1)。结论　紫癜肾儿童血、尿凝血纤溶系统平衡紊乱 ,表现为凝血亢进和纤溶障碍 ,干预性治疗具有一定疗效     

卡托普利和氯沙坦对自发性高血压大鼠纤溶功能的影响

目的:观察卡托普利和氯沙坦对自发性高血压大鼠(SHR)纤溶酶原激活物抑制剂-1(PAI-1)和组织型纤溶酶原激活物(t-PA)血浆活性及组织表达的影响。方法:SHR分为卡托普利组、氯沙坦组和对照组,用发色底物法测血浆PAI-1和t-PA活性,RT-PCR半定量法测组织表达。结果:SHR主动脉组织PAI-1表达增加,卡托普利(P<0.01)和氯沙坦(P<0.05)使PAI-1表达显著降低。结论:转换酶抑制剂卡托普利和血管紧张素II受体1拮抗剂氯沙坦可减少早期SHR主动脉PAI-1表达,改善局部的纤溶平衡和血管重构。     

三七皂苷Rg1对t-PA和PAI-1水平的影响

目的探讨三七皂苷Rg1对组织型纤溶酶原激活物(t-PA)和纤溶酶原激活物抑制物(PAI-1)水平的影响及其作用机制。方法运用发色底物法测定三七皂苷-Rg1在家兔体内、外对血浆纤溶酶原激活物(t-PA)和血浆或血小板释放的纤溶酶原激活物抑制物(PAI-1)水平的影响。结果三七皂苷-Rg1在体外能抑制血浆PAI-1活性,提高血浆t-PA活性,其作用强度呈现出剂量依赖性;静脉内给药显示:三七皂苷-Rg1 30、60、120和240 mg.kg-1组能降低血浆或血小板释放的纤溶酶原激活物抑制物(PAI-1)水平,增强血浆t-PA活性,而且本品还能降低激活的血小板所释放的PAI-1水平。结论三七皂苷Rg1能够有效对抗由于PAI-1活性增高和t-PA活性降低所引起的血栓,这可能是其具有抗血栓作用的有效机制之一。     

黄芪多糖对慢性血栓栓塞性肺动脉高压大鼠的抗血栓保护作用

目的 研究黄芪多糖(Astragalus polysaccharide, APS)对慢性血栓栓塞性肺动脉高压大鼠的保护作用及其通过抑制血小板活性抗血栓的作用及机制。方法 将SD大鼠随机分为4组,即：空白组、假手术组、模型组和黄芪多糖给药组。采用HE染色观察大鼠肺动脉中血栓的形成,检测4组大鼠血液的凝血4项水平,采用酶联免疫吸附(ELISA)法分别检测大鼠血浆中血栓素(TXA₂)、6酮前列腺素F1a(6-keto-PGF1a)、纤溶酶原激活物抑制剂-1(PAI-1)、组织型纤溶酶原激活剂(tPA)和尿激酶型纤溶酶激活物(uPA)的水平;制备血小板,检测不同激动剂下APS对血小板聚集和释放的影响;检测APS对血小板释放物TXA₂和PAI-1的影响。结果 与模型组相比,黄芪多糖给药组大鼠的平均肺动脉血压和血管壁面积/血管总面积(WA/TA)比值降低,血液凝血四项的水平降低,大鼠血浆中TXA₂和PAI-1的含量降低,而6-keto-PGF1a、tPA和uPA的含量升高。与对照组相比,APS孵育后的血小板聚集和释放降低,释放物TX...     

Amelioration of glomerulosclerosis with all-trans retinoic acid is linked to decreased plasminogen activator inhibitor-1 and α-smooth muscle actin

Aim:

To examine the effects of all-trans retinoic acid (atRA) on renal morphology and function as well as on renal plasminogen activator inhibitor-1 (PAI-1) expression and plasmin activity in rats with 5/6 nephrectomy.

Methods:

Adult male Sprague Dawley rats were given 5/6 nephrectomy or sham operation. Renal function was measured 2 weeks later. The nephrectomized rats were assigned to groups matched for proteinuria and treated with vehicle or atRA (5 or 10 mg/kg by gastric gavage once daily) for the next 12 weeks. Rats with sham operation were treated with vehicle. At the end of the treatments, kidneys were collected for histological examination, Western blot analysis, and enzymatic activity measurements.

Results:

The 5/6 nephrectomy promoted hypertension, renal dysfunction, and glomerulosclerosis. These changes were significantly reduced in the atRA-treated group. The expressions of PAI-1 and α-smooth muscle actin (α-SMA) were significantly increased in the vehicle-treated nephrectomized rats. Treatment with atRA significantly reduced the expressions of PAI-1 and α-SMA. However, plasmin activity remained unchanged following atRA treatment.

Conclusion:

Treatment with atRA ameliorates glomerulosclerosis and improves renal function in rats with 5/6 nephrectomy. This is associated with a decrease in PAI-1 and α-SMA, but not with a change in plasmin activity.     

来氟米特对肾大部切除大鼠肾皮质α-平滑肌肌动蛋白的影响

目的探讨来氟米特对肾大部切除大鼠肾脏功能的影响。方法将大鼠随机分为假手术组和手术组,术后3d再将手术组大鼠随机分为来氟米特组和模型组。8周后测尿蛋白和血肌酐;取肾组织做病理检查;用免疫组织化学检查肌成纤维细胞标志抗原———α-平滑肌肌动蛋白(α-SMA)。结果模型组大鼠肾脏出现肾小球硬化和肾间质纤维化;和假手术组相比α-SMA表达明显升高;来氟米特组肾脏纤维化明显减轻,α-SMA表达比模型组明显下降。结论来氟米特可抑制肌成纤维细胞增生和浸润,减轻肾脏纤维化从而保护肾功能。     

肾衰康2号抗肾纤维化及其尿毒素清除作用的研究

目的观察肾衰康2号对5／6肾切除大鼠所致慢性肾衰肠道清除尿毒素及其延缓肾脏纤维化的作用。方法将5／6肾切除大鼠分为肾衰康治疗组和对照组，并设假手术组为正常对照。普通喂养10周后检测各组的血清及粪便尿素氮、肌酐，并留取肾组织作病理，免疫组化法检测肾组织内纤维连接蛋白（FN）的表达水平。结果肾衰康2号治疗组血清尿素氮、肌酐较对照组下降（P〈0．05），粪便尿素氮、肌酐水平较对照组升高（P〈0．05），病理切片显示治疗组残余肾小球体积、直径与对照组相比明显减小（P〈0．05），肾小球系膜细胞、基质的增生程度亦明显减轻（P〈0．05），免疫组化显示，治疗组肾小球内FN的沉积比对照组减少（P〈0．05）。结论肾衰康2号有延缓肾纤维化，促进尿毒素排泄的作用。     

Modulation of PAI-1 and tPA activity and thrombolytic effects of corilagin

In this study, Charlton's and Tomihisa's methods were modified to investigate the thrombolytic effect of corilagin from the Chinese herbal plant Phyllanthus urinaria L., as well as its effect on carotid artery patency status. The activity of type 1 plasminogen activator inhibitor (PAI-1) in rat plasma or platelet-released substances and tissue-type plasminogen activator (tPA) in rat plasma was assayed by use of a chromogenic substrate. The results showed that corilagin had a dose-dependent thrombolytic effect in rats. 5 mg/kg of corilagin produced a nearly similar reperfusion rate to that of 20000 U/kg of urokinase, whereas it produced a lower reocclusion rate than urokinase. Corilagin significantly inhibited PAI-1 activity in rat plasma or platelet-released substances while it elevated plasma tPA activity, in a concentration-dependent manner. Corilagin, however, had no influence on rabbit platelet aggregation. It is indicated that corilagin inhibited PAI-1 activity and increased tPA activity, and this property of corilagin is assumed to be responsible for the thrombolytic effect. Abbreviations. PO:persistent occlusion CR:cyclic reflow PP:persistent patency PAI-1:type 1 plasminogen activator inhibitor tPA:tissue-type plasminogen activator PBS:phosphate buffer solution IC (50):50 % of inhibitory concentration PRP:platelet-rich plasma ADP:adenosine diphosphate AA:arachidonic acid PAF:platelet-activating factor     

Eprosartan effect on fibrinolytic/hemostatic variables in arterial hypertension: a comparative study to losartan

Essential hypertension is often accompanied by abnormalities of the coagulation/fibrinolytic system predisposing to a procoagulant state. The aim of the present study was to examine the comparative efficacy of the angiotensin II type 1 receptor antagonists eprosartan and losartan on plasma levels of hemostatic/fibrinolytic and endothelial function markers in a cohort of previously untreated hypertensive patients. A total of 86 patients whose hypertension was controlled by monotherapy with eprosartan 600 mg (45 patients) or losartan 100 mg (41 patients) were studied. The plasma levels of plasminogen activator inhibitor-1 (PAI-1) antigen, tissue plasminogen activator inhibitor (tPA) antigen, thrombomodulin (TM), tissue factor pathway inhibitor (TFPI) antigen, and fibrinogen were determined before and after 6 months of therapy. Age, sex distribution, body mass index, lipid profile, systolic and diastolic blood pressure levels, and baseline values of the measured markers were similar in both groups. After 6 months of therapy, systolic blood pressure was significantly lower in patients treated with eprosartan, while no differences were observed with respect to diastolic blood pressure. Treatment with both drugs was associated with a significant decrease in PAI-1 antigen, TM, fibrinogen plasma levels and an increase in tPA antigen. The favorable modification of all the above parameters was significantly greater in the eprosartan than in the losartan group, while TFPI plasma levels were decreased to a similar extent with both drugs. In conclusion, the results of our study indicate that 6-month monotherapy with a new angiotensin II type 1 receptor blocker, eprosartan, is associated with a more favorable modification of hemostatic/fibrinolytic status than with losartan.