参三七皂甙Rg1对实验性血栓形成的影响及其机制探讨

用大鼠动静脉血栓形成模型,研究参三七皂甙Rg₁抗血栓作用。结果表明,参三七皂甙Rg₁可明显降低实验性血栓形成,对大鼠血浆纤溶系统亦有明显作用,可升高血浆中组织纤溶酶原激活物(t-PA)活性和活性型t-PA百分比,降低组织纤溶酶原激活物抑制剂(PAI)活性。同时利用培养大鼠血管内皮细胞实验,发现Rg₁可以剂量依赖性提高血管内皮细胞一氧化氮(NO)释放。提示Rg₁抗血栓作用与增强纤溶系统活性,促进血管内皮NO释放有关。     

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。     

极化液对冠心病患者纤溶系统功能的影响

目的：观察极化液葡萄糖－胰岛素－氯化钾（ＧＩＫ）用于冠心病治疗时对纤溶系统功能的影响。方法：４６例确诊冠心病患者,其中陈旧性心肌硬塞１０例,不稳定性心绞痛１４例,稳定性心绞痛２２例。给予ＧＩＫ液,即１０％葡萄糖５００ｍｌ＋普通胰岛素１０μｌ＋氯化钾１ｇ静滴 ８～１２ ｄ。于用药前后测定组织型纤溶酶原激活物活性（ｔ－ＰＡ：Ａ）及其抑制物活性（ＰＡＬ：Ａ）,纤溶酶原活性（ＰＬｇ）,组织型纤溶酶原激活物（ｔ－ＰＡ）及其抑制物（ＰＡＩ－Ｉ）含量及Ｄ－二聚体（Ｄ－Ｄｉｍｅｒ）含量,空腹血清胰岛素水平。结果：用药前与正常比较,ｔ－ＰＡ活性降低,ＰＡＩ－１活性增高,胰岛素水平增高,高胰岛素者占７８．２％。用药后ｔ－ＰＡ活性及含量、纤溶酶原活性均较前降低（Ｐ＜０．０１）,ＰＡＩ－１含量较前增加（Ｐ＜０．００１）,而ＰＡＩ－１活性及Ｄ－Ｄｉｍｅｒ变化不明显。结论：冠心病特别伴有胰岛素水平增高患者,应用ＧＩＫ液可能通过其对纤溶系统功能的不良影响促使病变进展。     

三七皂苷组方对家兔血浆t-PA、PAI-1活性的影响

目的探讨三七皂苷组方对家兔血浆组织型纤溶酶原激活物(t-PA)、纤溶酶原激活物抑制剂-1(PAI-1)活性的影响,筛选出对家兔血浆有显著作用的药方。方法运用发色底物法测定不同三七皂苷组分在体外对家兔血浆释放纤溶酶原激活物(t-PA和纤溶酶原激活物抑制剂(PAI-1)水平的影响。结果新配方和三七总皂苷相比,有一个三七皂苷配方能提高血浆t-PA活性水平,另一个三七皂苷配方抑制血浆PAI-1活性。结论改变三七总皂苷中三七皂苷单体的含量,所得配方在功效上有很大的改变。     

蝎毒活性肽对内皮细胞释放t-PA和PAI的影响

血管内皮细胞 (ｖａｓｃｕｌａｒｅｎｄｏｔｈｅｌｉａｌｃｅｌｌｓ,ＶＥＣ)能合成和分泌组织型纤溶酶原激活物 (ｔｉｓｓｕｅｐｌａｓｍｉｎｏｇｅｎａｃｔｉｖａｔｏｒ ,ｔ ＰＡ) ,使纤溶酶原激活为纤溶酶 ,促进局部血栓溶解 ,ＶＥＣ还可分泌纤溶酶原激活物抑制剂 ( ｐｌａｓｍｉｎｏｇｅｎａｃｔｉｖａｔｏｒｉｎ ｈｉｂｉｔｏｒ,ＰＡＩ) ,当机体处于正常情况下ｔ ＰＡ与ＰＡＩ保持动态平衡 ,这对于维持血液纤溶和凝血系统的稳定至关重要 ,因此 ,血管内皮细胞在调节血栓的形成和溶解方面具有十分重要的作用。全蝎是名贵中药材 ,有祛风、…     

冠心病患者纤维激活系统功能改变的初步观察

对１８例不同类型的冠心病患者及６例正常人的血浆组织型纤溶酶原激活物及其抑制物的活性进行检测，结果表明，心肌梗塞后及不稳定性心绞痛患者ＰＡＩ－１活性显着增高，ｔＰＡ活性显著下降，ＰＡＩ－１／ｔＰＡ活性比值显着增高；稳定性心绞痛患者ＰＡＩ－１活性轻度增高，ｔＰＡ活性及ＰＡＩ１／ｔＰＡＩ活性比值变化不明显，全部受检者ＰＡＩ－１与ｔＰＡ活性具有显著线性负相关，提示冠心病纤溶激活功能减低，该损害可能具有冠心     

青心酮对妊高征模型兔血浆纤溶相关因子和血小板功能的影响

采用缩窄腹主动脉下段的方法造成家兔实验性妊高征模型，并采用比浊法和发色底物分解产色法检测了注射青心酮（３，４－Ｄｉｈｙｄｒｏｘｙａｃｅｔｏｐｈｅｎｏｎｅ，ＤＨＡＰ）的模型兔血小板聚集性（ＰＡｇ）、血浆组织型纤溶酶原激活物（ｔＰＡ）及其抑制物（ＰＡＩ－１）活性。结果显示ＤＨＡＰ可显著降低模型兔ＰＡｇ；对血浆ＰＡＩ－１活性的抑制作用明显强于对ｔＰＡ的作用，因此，ＤＨＡＰ对血小板功能和血纤溶活性的作用可能是其改善子宫胎盘血循环的作用机制之一。     

慢性肺心病急性发作期t—PA,PAI活性的变化

测定３２例肺心病急性发作期组织型纤溶酶原激活物（ｔ－ＰＡ）、纤溶酶原激活物抑制物（ＰＡＩ）、纤溶酶原（Ｐｇ）及纤维蛋白原降解产物（ＦＤＰ）。结果表明，肺心病患者ｔ－ＰＡ、ＰＡＩ、Ｐｇ明显下降，而ＦＤＰ明显升高，表明肺心病急性发作期处于高凝、低纤溶状态。ｔ－ＰＡ、Ｐｇ的变化与ＰａＯ２呈明显正相关，而ＦＤＰ与ＰａＯ２呈明显负相关。     

填精补血化瘀口服液对实验性动脉硬化鹌鹑纤溶活性的影响及机理研究

填精补血化瘀口服液具有升高食铒性动脉硬化（Ａｔｈｅｒｏｓｃｌｅｒｏｓｉｓ，ＡＳ）鹌鹑血浆组织型纤溶酶元激活物（Ｔｉｓｓｕｅｐｌａｓｍｉｎｏｇｅｎａｃｔｉｖｉｔｏｒ，ｔ－ＰＡ）活性，降低纤溶酶元激活物抑制物（Ｐｌａｓｍｉｎｏｇｅｎａｃｔｉｖｉｔｏｒｉｎｈｉｂｉｔｏｒ，ＰＡＩ）活性；调整二者活性比，恢复纤维系统功能，其作用机理可能与该方药减少动脉壁脂质沉积，改善血液流变性，减轻动脉内膜损伤，保护平滑肌     

填精补血化瘀口服液对实验性动脉硬化鹌鹑纤溶活性的影响及机理研究

填精补血化瘀口服液具有升高食饵性动脉硬化（Ａｔｈｅｒｏｓｃｌｅｒｏｓｉｓ，ＡＳ）鹌鹑血浆组织型纤溶酶元激活物（ＴｉｓｓｕｅＰｌａｓｍｉｎｏｇｅｎａｃｔｉｖｉｔｏｒ，ｔ－ＰＡ）活性，降低纤溶酶元激活物抑制物（Ｐｌａｓｍｉｎｏｇｅｎａｃｔｉｖｉｔｏｒｉｎｈｉｂｉｔｏｒ，ＰＡＩ）活性；调整二者活性比，恢复纤溶系统功能。其作用机理可能与该方药减少动脉壁脂质沉积，改善血液流变性，减轻动脉内膜损伤，保护平滑肌细胞及内皮细胞功能活动有关．因而，该方药对治疗ＡＳ，尤其是防止ＡＳ的恶化，都具有积极意义。     

卡托普利对大鼠t-PA和PAI-1活性的作用

目的评价卡托普利对大鼠血浆t-PA和PAI-1活性水平的影响。方法给大鼠应用三种剂量的卡托普利,观察其对大鼠血浆t-PA和PAI-1活性水平的作用。结果卡托普利治疗后使大鼠血浆t-PA活性升高,PAI-1活性及PAI-1/t-PA活性比值显著降低,这种作用呈某种程度的剂量依赖性。结论卡托普利能增强大鼠纤溶系统的活性,这种作用呈某种程度的剂量依赖性。     

年龄及人参皂甙 Rg1 对大鼠大脑皮层 NO 释放的影响

探讨了NO与衰老的关系及与Rg1抗衰老机制的关系。用Griess法,³H-L-精氨酸转化法分别研究大鼠大脑皮层细胞NO含量及NOS活性,观察其随龄变化及人参皂甙Rg1(Rg1)对老年鼠NO及NOS的影响。实验表明,成年鼠(9月龄)与青年鼠(3月龄)NO含量及NOS活性无显著性差异。老年鼠(27月龄)脑皮层NO含量明显高于青年鼠和成年鼠,NOS活性也明显增高。老年鼠给予Rg1后可显著减少大脑皮层NO含量和降低NOS活性。结果提示,NO与衰老关系密切,Rg1的抗衰老作用与其对NOS活性的抑制有关。     

Panax notoginseng and its components decreased hypertension via stimulation of endothelial-dependent vessel dilatation

Ginsenoside Rb1 and Rg1 are major components of Panax notoginseng (P.N.), an herb with known clinical efficacy in hypertension and myocardial ischemia in Eastern countries. This investigation is to elicit the mechanism of these components in hypertension via their effect on vascular reaction. To assess the ability of P.N. in hypertension, P.N. extracts were injected in spontaneously hypertensive rats (SHR) via the vena caudalis; Low dosages of P.N. extracts significantly lowered blood pressure in SHR. Examination with Rb1 and Rg1 revealed significant vasodilatation using mouse coronary arteries in a dose-dependent manner. Rb1- and Rg1-induced vasodilatation was blocked by pre-incubation with eNOS and PI3K inhibitors. Coronaries of eNOS-/- mice showed attenuated vasodilatation with Rb1 and Rg1. In addition, both Rb1 and Rg1 induce nitric oxide (NO) generation through increasing the phosphorylation of eNOS, activating Na+-independent l-arginine transport, and stimulating cationic amino acid transport (CAT)-1 mRNA expression in cultured endothelial cells. CONCLUSION: Ginsenoside Rb1 and Rg1 increased endothelial-dependent vessel dilatation through the activation of NO by modulating the PI3K/Akt/eNOS pathway and l-arginine transport in endothelial cells. These findings may have important implications for understanding the mechanisms of clinical efficacy of the herb P.N. when used in the regulation of blood pressure.     

Ginsenosides Rg3 and Rh2 inhibit the activation of AP-1 and protein kinase A pathway in lipopolysaccharide/interferon-gamma-stimulated BV-2 microglial cells

The anti-inflammatory effect of ginsenosides Rg3 and Rh2, which improves ischemic brain injury induced by middle cerebral artery occlusion, was investigated in lipopolysaccharide (LPS) and IFN-gamma-induced murine BV-2 microglial cells. Ginsenoside Rh2 inhibited the production of NO, with an IC50 value of 17 microM. The inhibitory effect of Rh2 on NO correlates with the decreased protein and mRNA expression of an inducible NO synthase (iNOS) gene. Additionally, ginsenoside Rh2 inhibited the expression of COX-2, pro-inflammatory TNF-alpha and IL-1beta in BV-2 cells induced by LPS/IFN-gamma, while it increased the expression of the anti-inflammatory cytokine IL-10. Electrophoretic mobility shift assays revealed that ginsenoside Rh2 significantly inhibited the LPS/IFN-gamma-induced AP-1 DNA binding activity, while it enhanced the protein binding to CRE sequences. However, it did not affect NF-kappaB binding activity. Thus, the anti-inflammatory effect of Rh2 appears to depend on the AP-1 and protein kinase A (PKA) pathway. The anti-inflammatory effect of ginsenoside Rg3 against LPS/IFN-gamma-activated BV-2 cells was less potent than that of ginsenoside Rh2. These findings suggest that the in vivo anti-ischemic effect of ginsenoside Rg3 may originate from ginsenoside Rh2, which is a main metabolite of ginsenoside Rg3 by intestinal microflora, and that of ginsenoside Rh2 may be due to its anti-inflammatory effect in brain microglia.     

Ginsenoside Rg3 inhibits phenylephrine-induced vascular contraction through induction of nitric oxide synthase

Ginsenoside Rg3 (Rg3) isolated from Panax ginseng relaxes vessels and exerts a cytoprotective effect. In view of the fact that nitric oxide (NO) is involved in vascular hyporeactivity and immunostimulation, the effects of total ginsenosides (GS) and Rg3 on the vascular responses and the expression of inducible nitric oxide synthase (iNOS) were investigated. Vasocontraction of endothelium-denuded aortic ring was induced by phenylephrine with or without GS or Rg3. The expression of iNOS was assessed by Western blot and RT-PCR analyses. NF-kappaB activation was monitored by gel shift, immunoblot and immunocytochemical analyses. Incubation of the endothelium-denuded aortic ring with GS or Rg3 inhibited phenylephrine-induced vasocontraction, which was abrogated by NOS inhibition. GS or Rg3 increased NO production in aortic rings, but Rb1, Rc, Re and Rg1 had no effect. Aortic rings obtained from rats treated with GS or Rg3 responded to phenylnephrine to a lesser extent, while producing NO to a larger extent, than those from control animals. GS or Rg3 induced iNOS in vascular smooth muscle. Rg3 induced iNOS with increase in NO production in Raw264.7 cells. Rg3 increased NF-kappaB DNA binding, whose band was supershifted with anti-p65 and anti-p50 antibodies, and elicited p65 nuclear translocation, which was accompanied by phosphorylation and degradation of I-kappaBalpha. PKC regulated iNOS induction by Rg3. In conclusion, Rg3 relaxes vessels as a consequence of NO production, to which iNOS induction contributes, and iNOS induction by Rg3 accompanied NF-kappaB activation, which involves phosphorylation and degradation of I-kappaBalpha and nuclear translocation of p65.     

Homoplantaginin modulates insulin sensitivity in endothelial cells by inhibiting inflammation

Recent data have indicated that inflammation plays an important role in the development of insulin resistance. The present study aims at examining the activity of homoplantaginin, a flavonoid from a traditional Chinese medicine Salvia plebeia R. BR., on palmitic acid (PA)-induced insulin sensitivity and the underlying mechanisms of its anti-infammatory properties in the endothelial cells. Pre-treatment of homoplantaginin on human umbilical vein endothelial cells (HUVECs) significantly inhibited PA induced tumour necrosis factor-α (TNF-α) and interleukin-6 (IL-6) mRNA expression, and inhibitory κB kinase beta (IKKβ) and nuclear factor-κB (NF-κB) p65 phosphorylation. To the PA-impaired insulin-dependent tyrosine phosphorylation of insulin receptor substrate-1 (IRS-1) and decrease in nitric oxide (NO) production, pretreatment of homoplantaginin could effectively reverse the effects of PA. Additionally, homoplantaginin significantly modulated the Ser/Thr phosphorylation of IRS-1, improved phosphorylation of Akt and endothelial nitric oxide synthase (eNOS), and increased NO production in the presence of insulin. Taken together, our results demonstrated that homoplantaginin ameliorates endothelial insulin resistance by inhibiting inflammation and modulating cell signalling via the IKKβ/IRS-1/pAkt/peNOS pathway, suggesting it may be used for the prevention and treatment of endothelial dysfunction associated with insulin resistance.     

Effect of NO2 exposure on antioxidant defense of endothelial cells

Nitrogen dioxide (NO2), an environmental oxidant pollutant, is toxic to lung cells. We evaluated the changes in antioxidant enzyme activities in porcine pulmonary artery (PA) and aortic (AO) endothelial cells in monolayer cultures. Confluent PA or AO endothelial cells were exposed to 3 or 5 ppm NO2 or air (control) for 3-24 h and assayed for GSH-reductase (GSH-red), GSH-peroxidase (GSH-per), and glucose-6-phosphate dehydrogenase (G6PDH) activities as well as for intracellular GSH content. After 3, 6, or 12 h exposure to 3 or 5 ppm, GSH-red and G6PDH activities were not different from those of controls in both PA and AO endothelial cells. Exposure to 3 or 5 ppm NO2 for 24 h resulted in significant increases in GSH-red (P less than 0.05) and G6PDH (P less than 0.001) activities in both cell types. GSH-per activity and GSH content in NO2-exposed PA and AO endothelial cells were not different from those of controls, irrespective of NO2 concentration and exposure time. These results indicate that enzyme activities of G6PDH and GSH-red are increased in PA and AO endothelial cells exposed to NO2, and this response is comparable, in part, to that in the lungs from animals exposed to NO2.     

人参皂苷Rg1对抗多巴胺对PC12细胞凋亡的诱导作用

通过测定细胞的凋亡率 ,内源性NO的水平和iNOSmRNA的表达及半胱天冬酶 3的活性 ,探讨人参皂苷Rg1对抗多巴胺对PC12细胞凋亡诱导作用的可能机理 .结果表明多巴胺 (0 .15～ 0 .60mmol·L- 1)可诱导PC12细胞凋亡 ,预先经过 10 μmol·L- 1Rg 1处理后 ,PC12细胞的凋亡率显著下降 (P <0 .0 0 1) ,同时NO2- 水平和iNOSmRNA表达水平及半胱天冬酶 3活力较单纯多巴胺处理组明显降低(P <0 .0 0 1) .结果提示 ,Rg1减少细胞内源性NO的生成及抑制半胱天冬酶 3的活化可能是Rg1对抗多巴胺诱导PC12细胞凋亡的重要机理 .