福辛普利对慢性肾功能衰竭幼鼠凝血纤溶变化的干预影响

目的探讨血管紧张素转换酶抑制剂(ACEI)——福辛普利干预治疗对幼年大鼠慢性进展性肾脏病变过程中肾组织组织型纤溶酶原激活物(tPA)、组织型纤溶酶原激活物特异性抑制剂(PAI)-1蛋白表达的影响。方法以5/6肾切除SD大鼠为实验动物模型,予ACEI治疗12周后分别检测大鼠体重、血压、血尿生化及残肾组织常规病理和用免疫组织化学染色定性定量评价残肾tPA、PAI-1蛋白表达。结果于5/6肾切除后,大鼠肾功能进行性丧失,表现为尿蛋白、血压、血尿素氮(BUN)、肌酐(Scr)及血脂增高,残肾组织出现肾小球硬化和间质纤维化。免疫组织化学染色提示肾组织PAI-1表达增高,而tPA表达下降。经ACEI治疗后,大鼠肾功能改善、血压下降、尿蛋白下降、残肾组织tPA蛋白表达增加、PAI-1表达下降。结论ACEI具有改善5/6肾切除大鼠凝血纤溶系统紊乱的作用。     

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。     

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.     

细胞外基质微环境变化及其与肾纤维化关系的研究现状

肾纤维化(renal fibrosis)主要表现为肾间质纤维化(renal interstitial fibrosis)及肾小球硬化(gromerulosclerosis)两方面,主要特征为肾小管和间质毛细血管的丧失及细胞外基质(Extracellular matrix,ECM)的过度积聚.各种肾脏疾病发展至肾纤维化,与调控ECM代谢的ECM降解酶类-纤溶酶原激活物/纤溶酶原激活物抑制物(PAs/PAIs)以及基质金属蛋白酶/基质金属蛋白酶抑制物(MMPs/TIMPs)的表达与活性异常所导致细胞外基质微环境的变化密切相关,因此,明确PAs/PAIs与MMPs/TIMPs系统在肾纤维化发生发展过程中作用,有助于解析其遗传与分子调节机制,进而干预ECM降解酶的活性或表达,达到防治肾纤维化的目的.     

芪红合剂对肾间质纤维化模型大鼠的实验研究

目的探讨芪红合剂对肾间质纤维化的防治作用。方法采用单侧输尿管结扎致肾间质纤维化动物模型,以公认有肾脏保护作用的血管紧张素转换酶抑制剂(ACEI)为阳性对照,测血肌酐(Scr)、尿素氮(BUN),免疫组织化学法测肾组织纤维蛋白溶解酶原激活物抑制因子(PAI)-1、纤维连接蛋白(FN)的表达。结果芪红合剂能降低血BUN、Scr水平,显著抑制PAI-1、FN的表达,减轻肾间质纤维化程度。PAI-1分别与FN、肾间质纤维化面积显著相关。肾间质纤维化面积分别与BUN、Scr相关。结论芪红合剂有早期防治肾间质纤维化作用。     

t-PA、PAI-1在慢性肾小球肾炎中的表达及意义(附58例分析)

目的探讨组织型纤溶酶原激活物（t-PA）及1型纤溶酶原激活物抑制物（PAI-1）在慢性肾小球肾炎中的表达及意义。方法用酶联免疫吸附双抗体夹心法测定t-PA、PAI-1活性。结果慢性肾小球肾炎患者治疗前组的t-PA活性明显低于治疗后组，并有极显著性差异（P〈0．01），治疗后病人症状好转；慢性肾小球肾炎患者治疗前组的PAI-1活性明显高于治疗后组，并有显著性差异（P〈0．01），治疗后病人症状好转或痊愈。结论t-PA、PAI-1作为两项肾小球纤维化指标，其活性测定对在临床中跟踪了解慢性肾小球肾炎患者的病情及预后、指导抗纤维化治疗具有重要的临床意义。     

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。     

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     

机械拉伸对人Ⅱ型肺泡上皮细胞表达纤溶酶原激活物抑制剂-1的影响

<正>机械通气(MV)是重危患者治疗、手术全麻必不可少的治疗手段。机械通气也能激活肺组织炎症级联反应,促进炎性细胞因子释放,诱发肺损伤(VILI)[1]。VILI相关的生物伤一直为国内外研究者关注的重点[2,3],其致病机制复杂,有待于进一步阐明。纤溶酶原激活物抑制剂-1(PAI-1)是纤溶的调节剂(u PA),在肺部炎症中也发挥重要的作用[4,5]。本研究拟通过对机械拉伸A549细胞PAI-1表达的影响,探讨机械通气     

Effects of polysulfated glycosaminoglycan and triamcinolone acetonid on the production of proteinases and their inhibitors by IL-1alpha treated articular chondrocytes

In this study we determined the in vitro effects of polysulfated glycosaminoglycan (PSGAG) and the glucocorticoid triamcinolone acetonid (TA) on the IL-1 altered expression and activity of matrix metalloproteinases (MMP-1, MMP-3), tissue inhibitor of metalloproteinases-1, the plasminogen activators tPA and uPA and plasminogen activator inhibitor 1 by articular chondrocytes. Bovine chondrocytes were cultured in alginate gel beads. Cells were treated with interleukin-1alpha (IL-1alpha) in the presence of vehicle or drugs at various concentrations. After 48hr mRNA expression of MMP-1, MMP-3, TIMP-1, uPA, tPA and PAI-1 was analyzed by RT-PCR-ELISA. The protein synthesis of TIMP-1 and MMP-3 was determined by immunoprecipitation, PAI-1 protein was quantitated by ELISA. The activity of enzymes and inhibitors was measured by functional assays. Treating chondrocytes with IL-1 induced the expression of MMPs and downregulated TIMP-1 but stimulated both the expression of PAs and PAI-1. Both drugs significantly reduced collagenase and proteoglycanase activities which was accompanied by inhibition of the expression of MMP-1 and MMP-3. The IL-1 decreased expression of TIMP-1 was further reduced by TA, which resulted in a significant loss of TIMP activity. No effects on TIMP activity or TIMP-1 biosynthesis were observed after treatment of chondrocytes with PSGAG. Both drugs inhibited the IL-1-induced mRNA expression of tPA, whereas expression of uPA was only mildly reduced by PSGAG, which also induced PAI-1 above IL-1 stimulated levels. As inhibition of collagenase activities and tPA expression by PSGAG occurred at physiological concentrations it might be of clinical relevance, indicating that PSGAG could help reducing cartilage degradation and has a strong anti-fibrinolytic potential. Due to their co-regulation of MMPs and TIMP(s) glucocorticoids should be carefully studied for their overall effect on extracellular matrix proteolysis.     

Adipocytes derived fibrinolytic components in peritoneum — a pilot study

The proteins of the fibrinolytic system — urokinase plasminogen activator(uPA), tissue plasminogen activator (tPA)and plasminogen activator inhibitor type IPAI-I) — play important roles in fibrotization in various organs and including peritoneum. To study the cellular localization of PAI-1, tPA and uPA within the adipose tissue of the peritoneal membrane in patients at the onset of peritoneal dialysis(PD) we determined the initial expression of these proteins in relationship to multiple clinical variables. Methods: routinely performed parietal peritoneal biopsies in 12 patients undergoing peritoneal catheter implantation were examined. We used formalinfixed, paraffin-embedded specimens for immunohistochemical localization of these proteins along with the stereological pointcounting method for quantification of their expression within the peritoneal adipose tissue. Results: strong positive mutual correlation between the expression of PAI-1 and both uPA (SpearmanR=0.66) and tPA (R=0.59) as well as between the expression of uPA and tPA (R=0.77) was found without any relatioship to BMI, age, peritoneal transport characteristic or diabetes status. Conclusion: Adipose tissue within the peritoneum is capable of producing fibrinolysis regulators (independently on clinical parameters) thus possibly affecting the fibrotization and function of peritoneum as dialysis membrane. The effect of dialysis solution dosing, composition and other dialysis related factors should be clarified in future studies.     

Alteration in ovarian gene expression in response to 2,3,7,8-tetrachlorodibenzo-p-dioxin: reduction of cyclooxygenase-2 in the blockage of ovulation

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a reproductive toxicant and endocrine disrupter that is known to block ovulation. This study was designed to investigate alterations in relevant ovarian genes that may be involved in the blockage of ovulation by TCDD in immature intact rats primed with equine chorionic gonadotropin (eCG). In this ovulation model, rats were given either 32 microg/kg TCDD or corn oil by gavage on 25 days of age. The next day, eCG (5 IU) was injected subcutaneously (s.c.) to stimulate follicular development. Ovulation occurs 72 h after administration of eCG in controls of this model. TCDD blocked ovulation at the expected time and also reduced both ovarian and body weights. At 72 h after eCG (the morning after expected ovulation), TCDD did not alter significantly serum concentrations of progesterone (P4) and androstenedione (A4). However, estradiol (E2) was significantly higher at 72 h after eCG in TCDD-treated rats when compared with controls. Western blots revealed that ovarian CYP1A1 was induced by TCDD. In addition, the aryl hydrocarbon receptor (AhR) and AhR nuclear translocator (ARNT) were down- and up-regulated by TCDD, respectively, indicating that AhR-mediated signal transduction was altered in the ovary. Ovarian estrogen receptor (ER)alpha, ER beta and progesterone receptor (PR) were not altered significantly by TCDD, but ovarian glucocorticoid receptor (GR) was increased at 24h after TCDD and decreased at 72 h after eCG when compared with controls. TCDD induced the early appearance of ovarian plasminogen activator inhibitor type-1 (PAI-1), plasminogen activator inhibitor type-2 (PAI-2), urokinase plasminogen activator (uPA), and tissue plasminogen activator (tPA) at 24h after dosing when compared with controls. On the morning after ovulation (72 h after eCG), no significant differences between control and TCDD-treated rats were observed except that TCDD had still increased tPA and decreased PAI-2 when compared with controls. Interestingly, ovarian COX-2 was induced on the morning after ovulation (72 h after eCG) in controls, but was greatly inhibited in TCDD-treated rats at that time. On the other hand, COX-1 was constitutively expressed throughout the ovulatory period and remained unaffected by TCDD. Immunolocalization of COX-2 in the ovary revealed that TCDD inhibited COX-2 expression in the granulosa cell layer when assessed in the morning of expected ovulation. In conclusion, AhR signaling is activated in the ovary by TCDD and inhibition of COX-2 appeared to be a critical step in the TCDD blockage of ovulation because blockage or reduction of COX-2 expression is well known to be associated with failure of ovulation.     

tPA, but not uPA, significantly affects antithrombotic therapy by a glycoprotein IIb/IIIa antagonist, but not by a factor Xa inhibitor

To define the interaction of fibrinolytic components with platelets or coagulation factors on thrombus formation, we investigated mouse deficient in tissue plasminogen activator (tPA -/-) or urokinase plasminogen activator (uPA -/-) and in their wild-type control (tPA +/+, uPA +/+). A thrombus was induced in the murine carotid artery using photochemical reaction. Blood flow was monitored and the time needed before the vessel became completely obstructed was within 12 min in all types of mice. When DX-9065a, a selective factor Xa inhibitor, or GR144053, a platelet glycoprotein (GP) complex IIb/IIIa antagonist was applied, the time required to occlusion was prolonged in a dose-dependent manner in all types of mice. When a factor Xa inhibitor was injected in tPA -/- mice, the estimated ED50 was not changed. However, when GR144053 was injected in tPA -/- mice, the most significant changes were observed: the estimated ED51 was 19.6 times higher than the one in tPA +/+ mice. Platelet aggregation, hemostasis tests, and bleeding times were not significantly different among the different types of mice. In conclusion, the antithrombotic effect of platelet inhibition by a GPIIb/IIIa antagonist, is severely affected by the absence or presence of tPA production. On the contrary, the inhibition of factor Xa shows a stable antithrombotic effect with or without tPA. Thus the lack of tPA, but not of uPA, significantly affects antithrombotic efficacy.