血浆同型半胱氨酸对冠心病患者血管内皮功能的影响

目的 :探讨同型半胱氨酸 （Hcy）对冠状动脉粥样硬化患者血管内皮分泌功能的影响及可能机制。方法 :采用高效液相色谱法测定 5 7例冠状动脉粥样硬化患者和 40例健康体检者空腹血浆 Hcy水平 ,放射免疫法测定血浆内皮素 （ET） ,同时测定血浆一氧化氮 （NO）、丙二醛 （MDA）、超氧化物歧化酶 （SOD）水平。结果 :1冠心病患者伴或不伴高同型半胱氨酸血症空腹血浆 Hcy,ET,MDA水平均高于健康对照组 ,NO,SOD水平则低于健康对照组。 2冠心病患者中 ,高 Hcy血症组 ET水平略高于非高 Hcy血症组 ,NO水平较非高 Hcy血症组低 ,两亚组间 MDA,SOD水平无明显差异。结论 :高 Hcy血症可促进冠心病患者血浆 ET水平增高 ,NO水平降低 ,加重血管内皮功能紊乱。本研究不支持 Hcy通过氧化应激抑制损伤人体血管内皮功能的假说。     

内皮一氧化氮合酶在内皮细胞迁移中的作用

业已显示,内皮诱导的一氧化氮(NO)及其前身L-精氨酸可以促进血管生成,但对其精确机理现了解甚少.N-氮-L-精胺酸乙酯(L-NAME,1mmo/L)能抑制内源性的NO生成,进而抑制家牛主动脉内皮单层细胞边缘的内皮细胞胚芽,而其非活性的对映体D-NAME(1mmol/L)则不能抑制内源性的NO生成.L-NAME能抑制内源性的NO释放,已由NO专用电极通过安培计测量得到证实.在改进的Boyden舱内,L-NAME(1mmol/L)能显著地抑制内皮细胞的迁移.但根据[a~3H]胸腺嘧啶核甙混合物分析评价,L-NAME并不影响内皮DNA的合成.然后,我们用L-NAME在人体脐静脉内皮细胞中抑制NO,并检测内皮细胞粘着分子表达式的变化.在正常氧和低氧环境中,L-NAME(1mmol/L)能抑制粘合家分子,αvβ_3的表面表达.αvβ_3是促进内皮细胞存活和血管生成的一种重要的粘合素分子.然而,L-NAME并不影响血小板内皮细胞粘着分子-1,细胞间粘着分子-1,血管内皮粘着分子-1,间隙连接蛋白43,以及VE-钙粘附因子的表达,据报道这些分子可能影响血管生成.总之,L-NAME抑制内皮NO合酶可以减离体内皮细胞的迁移,但不能使其增生,进而,内源性内皮诱导的NO能维持粘合素分子αvβ_3的功能表达,αvβ_3是内皮迁移、存活和血管生成的递质.所以,内皮诱导的NO通过粘合素因子依赖机制,在支持内皮细胞迁移和     

急性冠脉综合征应用低分子肝素与普通肝素后血清浓度变化的比较

目的：了解低分子肝素与普通肝素皮下注射后药代动力学变化及临床的关系。方法：急性冠脉综合征患者29例，其中14例患者接受肝素钠6250U，15例患者接受低分子肝素4100U（速避凝0.4ml)腹部皮下注射，注射前及注射后30min,1、2、4、8、12h测血浆肝素浓度（Hep),Xa因子浓度，凝血酶原时间（PT）、凝血酶时间（TT）、部分凝血酶原时间（APTT），以及及纤维蛋白原（FIB）。结果：肝素皮下注射后30min即可见到血浆中肝素浓度上升，作用高峰时间为4h,8h时基本恢复正常（P＜0．01），血浆肝素浓度从小于0．01U／ml上升至4h的0．11U/ml（平均）。同时PT、TT、APTT也同步上长升。肝素与PT、TT、APTT的相关系数分别为0．49、0．723、0．708（P＜0．01），低分子肝素皮下注射后，血浆Xa因子浓度上升较为平稳，1h与8h时的Xa因子浓度无明显差异，12h时血浆中仍有一定浓度的Xa因子，于用药前相比P＜0．05）。但PT、TT、APTT基本不变，与血浆Xa因子无明显关系，结论：肝素皮下注射后，其药代动力学变化比较快，对凝血因子影响因素，但不稳定，低分子肝素皮下注射后，血浆中Xa因子的变化较为稳定，对凝血因子无明显影响。在皮下注射时应首选低分子肝素。     

脂联素对血管内皮功能的影响

目的 探讨脂联素对内皮功能的影响。方法 体外培养人脐静脉内皮细胞（HUVEC），观察脂联素对HUVEC在基础状态和肿瘤坏死因子α（TNF—α）刺激下的NO合酶（NOS）、NO和内皮素1（ET—1）的变化。结果 （1）脂联素未改变基础的内皮NO和总NOS活性（均P〉0．05），可部分依赖磷酸肌醇3激酶（PI3K）途径抑制iNOS活性（P〈0．05），增强cNOS活性（P〈0．01）。（2）脂联素可能依赖于核转录因子（NF）-κB途径抑制TNF—α刺激的iNOS的活性和NO、ET—1的释放（P〈0．01），脂联素逆转TNF—α对cNOS的抑制（P〈0．01）依赖于非NF—κB途径。结论 脂联素通过影响内皮细胞NOS活性，NO和ET-1的分泌，维持正常内皮细胞的功能，并对抗TNF—α损伤内皮细胞。     

血管内皮生长因子对培养内皮细胞合成一氧化氮的影响

目的 :探讨血管内皮生长因子 （VEGF） /血管渗透因子 （VPF）对内皮细胞 （EC）分泌一氧化氮 （NO）的影响。方法 :将培养的人脐静脉内皮细胞 （HUVEC）随机分为 6组 （n=6 /组 ） :1正常对照组 ;2 VEGF 1ng/ m l;3VEGF 10ng/ m l;4VEGF 10 0 ng/ m l;5低氧组 ;6低氧组 +VEGF 10 0 ng/ m l。采用硝酸还原酶法测定培养液中的 NO2 - ,NO3 -的含量以反映 NO水平。结果 :VEGF促进正常 EC分泌 NO,在一定浓度范围内呈剂量依赖性 ;低氧损伤 EC,使其分泌 NO减少 ;VEGF 10 0 ng/ ml预处理可保护 EC免受低氧损害 ,保持正常分泌 NO的功能。结论 :VEGF能够调节 EC的功能 ,为其促血管形成作用中 EC分裂、增殖、迁移奠定物质基础     

NO在心血管病中的临床意义

1980年FttChgott等”’在血管内皮细胞中发现的血管内皮舒张因子（EDRF）具有舒张血管、降低血压、抑制血管平滑肌细胞增殖和血小板粘附等重要的生理作用，现已证实就是NO。近年来，人们对NO在心血管系统中的分布、生理功能及心血管病中的关系进行了深入广泛的研究。IN0生理作用NO是由L一精氨酸（L－Arg）和分子氧在NO合成酶（NOS）催化下生成的，NOS则是NO生成的关键酶，NO的半衰期仅约6S，迅速转化为较稳定的代谢产物亚硝酸／硝酸根离子（N07／NOI）。能合成和释放NO的细胞包括内皮细胞、白细胞、单核／巨噬细胞、肝细胞、…     

抵抗素对内皮细胞NO生成的影响及Akt信号机制

目的探讨抵抗素对内皮细胞NO生成的影响及其可能的信号机制。方法分离、培养人脐静脉内皮细胞（HUVECs）,以不同浓度抵抗素（15、50、100ng／ml）干预。荧光显微镜检测各组细胞中N0的生成,RT-PCR检测eNOS mRNA表达水平,Western blot检测Akt和eNOS磷酸化水平。结果15、50、100ng／ml抵抗素干预HUVECs 24h后,胰岛素刺激的内皮NO生成显著降低（三组分别为4．01±0．69、3．764±0．71、3．73±0．45,vs对照组P均〈0．05）,同时伴有内皮Akt和eNOS磷酸化水平的降低（us对照组P均〈0．05）,而eNOS mRNA表达无显著改变。结论抵抗素可通过P13K／Akt途径影响HuVECs eNOS磷酸化水平,进而调节内皮细胞NO生成,但该影响并非Akt依赖性。     

蜈蚣对动脉粥样硬化家兔血管内皮细胞生长因子的影响

目的：从内皮细胞功能角度探讨中药蜈蚣对动脉粥样硬化（AS）家兔一氧化氮（NO）、内皮素（ET）以及血管内皮细胞生长因子（VEGF）表达的影响。方法：采用高脂饲喂家兔，建立动脉粥样硬化模型。随机分为4组，每组8只，造模过程中预防性给予蜈蚣治疗。（1）对照组：基础饲料＋5mg/kg蒸馏水灌胃；（2）模型组：高脂饲料＋5mg/kg蒸馏水灌胃；（3）蜈蚣小剂量组：高脂饲料＋蜈蚣水提物2．5g/kg灌胃；（4）蜈蚣大剂量组：高脂饲料＋蜈蚣水提物5g/kg灌胃。4组均饲喂12周。观察血清NO、ET的变化，采用流式细胞术及免疫荧光技术检测VEGF的表达量，并观察其主动脉血管病理。结果：模型组VEGF的表达量升高，经5g/kg蜈蚣治疗后，VEGF的表达量明显下调，NO释放增加，ET分泌减少，与模型组比较有统计学意义（P＜0．01）。而2．5g/kg蜈蚣对VEGF的影响无明显变化，表明蜈蚣对AS血管内皮细胞生长因子的影响存在一定的量效关系。结论：蜈蚣可通过调节NO／ET的平衡，从而抑制VEGF的表达，提示蜈蚣具有保护血管内皮细胞，防治内皮细胞增生的作用，揭示了中医血瘀证存在的微观物质基础，为中药蜈蚣抗动脉粥样硬化的临床应用提供了理论依据。     

血管紧张素转化酶基因多态性与内皮功能的研究

目的 :探讨血管紧张素转化酶 （ACE）基因多态性与冠心病血管内皮功能的关系。方法 :采用多聚酶链反应（PCR）技术对 2 4例心肌梗死、5 6例心绞痛患者、6 5例正常人的 ACE基因型及血浆内皮素 （ET）、内皮源性舒张因子 （EDRF）进行了检测 ,以 ET/ NO作为内皮功能指标。结果 :心肌梗死组 D等位基因频率显著高于正常对照组 ,DD型患者中的 ET/ NO比值较 型明显升高 （P<0 .0 5 ）。结论 :DD型心肌梗死患者内皮功能受损较重。     

缺氧条件下血管活性因子对血管内皮细胞中血管内皮生长因子表达的影响

目的　探讨在缺氧条件下人脐静脉血管内皮细胞血管内皮生长因子 (VEGF)表达及缩血管活性物质内皮素 ,舒血管活性物质NO和NO抑制剂LNNA对VEGF基因表达的影响。方法　体外培养人脐静脉血管内皮细胞 ,经缺氧及血管活性物质处理 ,Northern杂交、酶联免疫检测和计算机图像分析等观察VEGFmRNA和蛋白表达水平。结果　缺氧 6h内皮细胞可见VEGF表达。ET可促进VEGFmRNA的表达 ,NO可明显抑制VEGFmRNA的表达 ,NO抑制剂LNNA也影响VEGFmRNA的表达。ELISA检测VEGF蛋白水平分别为 6h组 (8 2± 1 1) μg/L ,ET +6h组 (9 37± 1 0 2 ) μg/L ,NO +6h组 (2 86± 0 91) μg/L ,LNNA +6h组 (14 75± 1 87)μg/L。 结论　缺氧可诱导人脐静脉血管内皮细胞分泌VEGF并受血管活性物质的调控 ,ET促进其表达 ,NO抑制其表达。     

The in vitro effect of a low molecular weight heparin, nadroparin (Fraxiparine), on leukocytes obtained from patients with vascular diseases.

BACKGROUND: Both lymphocytes and granulocytes may play a role in the immune system-mediated inflammatory response associated with non-Q wave infarction and aortic aneurysms. METHODS: The purpose of this study was to establish the in vitro effects of a low molecular weight heparin (LMWH), nadroparin (Fraxiparine), on some functional parameters of peripheral granulocytes and lymphocytes isolated from control subjects and patients with aortic aneurysm or non-Q wave infarction. RESULTS: Nadroparin (0.06-600 AXaU/ml) exerted different in vitro effects on granulocytes and lymphocytes isolated from normal subjects and the patient groups. The following indices were assessed: superoxide anion release, lymphocyte proliferation, phagocytic activity and the cellular respiratory burst. The effects of nadroparin varied according to the patient group and the index of lymphocyte/granulocyte assessed. CONCLUSIONS: Since peripheral granulocytes isolated from these patients are activated, the observed inhibition exerted by nadroparin on superoxide anion release may be beneficial. LMWHs have additional effects that are independent of their anticoagulant activity. These effects may influence the "inflammatory component" of the atherosclerotic process.     

低分子肝素治疗不稳定型心绞痛的疗效及其对内皮功能的影响

目的 研究低分子肝素（LMWH）治疗不稳定型心绞痛（UA）的疗效及其对血管内皮功能的影响。方法 将44例UA患者随机分为A、B两组，B组予常规治疗，A组在其基础上加用LMWH5000IU,1次／12h，腹部皮下注射，疗程为一周。观察心绞痛缓解、缺血性心电图改善及血浆内皮素（ET）、血管性假血友病因子（vWF)的变化。结果 缓解心绞痛的疗效A组优于B组（P＜0.05)；治疗前两组ET、vWF含量比较，差异无显著性（P＞0.05)，但均高于对照组（P＜0.001)，治疗后两组ET、vWF含量均下降，A组降低程度较B组显著（P＜0.05)。结论 LMWH缓解UA患者的心绞痛症状与血管内皮功能改善有一定关系。     

凝血酶通过内皮素介导刺激肾小球系膜细胞增生

研究内皮素－１在凝血酶刺激有肾小球系膜细胞增生中的作用。方法在培养肾小球系膜细胞中进行试验。（１）ＨＭＣ在凝血酶刺激下增生,呈剂量依赖并与刺激时间有关,当凝血酶１６Ｕ／ｍｌ刺激１６小时时ＨＭＣ增生达高峰;     

Inhibitory effect of C-reactive protein on the release of tissue factor pathway inhibitor from human endothelial cells: reversal by low molecular weight heparin.

AIM: The effects of C-reactive protein (CRP) and low molecular weight heparin (LMWH) on the release of tissue factor pathway inhibitor (TFPI) from human umbilical vein endothelial cells (HUVECs) were examined. METHODS: Confluent HUVECs were resuspended and plated in 48-well plates coated with fibronectin polymer. Cells were allowed to attach for 3 h; they were then washed, and fresh medium with or without CRP at different concentrations (0 to 20 ng/mL) was added. At 4 h, TFPI released in the medium was measured using a commercial TFPI ELISA kit for total TFPI antigen. In parallel assays, wells containing HUVECs and CRP were treated with tinzaparin at 1 mg/mL. RESULTS: Data showed that CRP significantly inhibited TFPI release from HUVECs in a concentration-dependent manner. In contrast, LMWH increased endothelial TFPI release. The amount of endothelial TFPI released was dependent on the heparin molecular weight distribution, with minimal effect at 3000 Da and maximum at 8000 to 12,000 Da. LMWH effectively reversed the inhibitory effects of CRP on TFPI release from HUVECs. CONCLUSIONS: These findings support the hypothesis that CRP may play a direct role in promoting a hypercoagulable state by decreasing the release of the natural anticoagulant TFPI, which can be counteracted by LMWH.     

Effects of antihypertensive drugs on alcohol-induced functional responses of cultured human endothelial cells.

Alcohol-induced endothelial changes might contribute to an increase in blood pressure in regular alcohol consumers. Some antihypertensive drugs affect oxidative stress and endothelial function and might counteract the effects of alcohol at the cellular level. The aim of this study was to investigate in vitro the effects of three different types of antihypertensive agents on alcohol-induced endothelial responses and oxidative stress. Cultured human endothelial cells were exposed to increasing concentrations (1, 10, 60 micromol/L) of zofenoprilat, carvedilol, and lacidipine in the absence and in the presence of ethanol (140 mmol/L). Concentrations of endothelin (ET) and nitric oxide (NO) were measured in the culture media as markers of endothelial function, and malondialdehyde (MDA) and intracellular glutathione (GSHi) were measured as markers of oxidative stress. Exposure to alcohol increased the levels of ET, NO, and MDA, and decreased GSHi. Carvedilol and zofenoprilat were more effective than lacidipine in counteracting the effects of alcohol on ET production. Alcohol-induced NO production was enhanced by carvedilol, whereas zofenoprilat and lacidipine did not have a significant effect. The alcohol-induced increase in MDA concentrations was blunted by all three drugs, but only carvedilol restored a normal response. All three drugs increased GSHi levels, with the effect being greater for carvedilol and lacidipine than zofenoprilat. Carvedilol is more effective than zofenoprilat and lacidipine in counteracting alcohol-induced endothelial responses in vitro and in decreasing oxidative stress. These effects might be particularly beneficial in patients with alcohol-related hypertension.     

卡维地洛对急性心肌梗死患者内皮功能及氧化指标的影响

目的观察卡维地洛对急性心肌梗死(AMI)患者血管内皮依赖性舒张功能及血清氧化指标——丙二醛(MDA)的影响。方法将52例AMI患者随机分成卡维地洛治疗组(28例)和常规治疗组(24例),比较观测治疗8周前后超声检测肱动脉流量介导性扩张的血管内皮依赖舒张功能及血清MDA的变化。结果治疗前两组比较,内皮依赖性血管舒张功能差异无统计学意义;卡维地洛治疗8周后内皮依赖性血管舒张功能明显改善;血清MDA水平明显降低,与治疗前比较,差异均有统计学意义(P<0.05或P<0.01)。结论卡维地洛在治疗8周后通过降低血清MDA水平的抗氧自由作用,可明显改善AMI患者血管内皮依赖舒张功能。     

Targeted delivery of heparin and LMWH using a fibrin antibody prevents restenosis

This study investigates a stent-less local delivery system for anti-restenotic agents utilizing antibodies to cross-linked fibrin (XLF). Heparin and low molecular weight heparin (LMWH) were conjugated to an antibody to cross-linked fibrin D-dimer (1D2). Rabbit right carotid arteries were injured with a balloon catheter, then the animals were given a bolus injection of 40 microg/kg 1D2-heparin (26-70 microg/kg heparin) or 1D2-LMWH (29-80 microg/kg LMWH) conjugates or controls of saline (0.5 ml/kg), heparin (150 U/kg), LMWH (2 mg), or 1D2 (40 microg/kg), with or without a heparin bolus and sacrificed after 2 weeks (8 groups, n = 6/group). The injured artery of rabbits given 1D2-heparin or 1D2-LMWH conjugates had reduced neointimal development, with decreased luminal narrowing and positive remodelling compared with animals given control drugs. Animals given 1D2-heparin conjugate (with a heparin bolus) had three to five times more endothelial cells than the rabbits given saline or unconjugated heparin, while rabbits given 1D2-LMWH conjugate had up to 59% fewer neointimal cells than those given unconjugated drugs. There was little difference in extracellular matrix organization or composition. Thus cross-linked fibrin-antibodies can site-deliver anti-restenotic agents to injured areas of the artery wall where they influence wall remodelling and endothelial and neointimal cell number, reducing neointimal formation without systemic complications. Local delivery of anti-restenotic agents should minimise systemic effects, bleeding complications and potentially the cost of treatment due to a single, lower dose.     

丹参注射液降低血管内皮细胞氧化应激损伤，对心肌梗死患者心肌功能的保护效果

目的:探讨丹参注射液降低血管内皮细胞氧化应激损伤,对急性心肌梗死(AMI)患者心肌功能的保护效果。方法:120例行经皮冠脉介入治疗(PCI)的AMI患者被随机均分为常规治疗组和丹参组(在常规治疗组基础上加用丹参注射液),两组均治疗14d。治疗前后检测比较两组外周血超氧化物歧化酶(SOD)、丙二醛(MDA)、一氧化氮(NO)、诱导型一氧化氮合酶(iNOS)、高敏心肌肌钙蛋白T (hscTnT)、肌酸激酶同工酶(CK-MB)及LVEF、心肌梗死面积,并随访观察两组术后3个月内主要不良心血管事件(MACE)和用药不良反应发生情况。结果:与常规治疗组治疗后比较,丹参组外周血SOD水平[(20.76±1.58)U/ml比(25.81±1.45)U/ml]、LVEF [(52.44±6.74)%比(57.57±4.39)%]显著升高,外周血MDA [(8.84±0.47)pg/ml比(6.74±0.56)pg/ml]、NO [(19.11±1.58)μmol/L比(15.34±1.74)μmol/L]、iNOS [(80.37±1.65)U/ml比(73.28±2.76)U/ml]、hscTnT [(38.25±4.24)ng/ml比(26.85±3.23)ng/ml]、CK-MB [(63.26±5.64)U/L比(32.68±4.49)U/L]水平以及心肌梗死面积[(19.42±4.33)mm2比(13.58±3.25)mm2]均显著降低,P均=0.001。术后随访3个月,丹参组MACE发生率显著低于常规治疗组(20.00%比41.67%),P=0.010。两组治疗过程中,均无严重药物不良反应发生。结论:丹参注射液能够显著减轻AMI患者PCI术后血管内皮细胞氧化应激损伤,保护缺血再灌注心肌功能,改善预后,值得推广。     

Pericardial fluid and serum VEGF in response to different types of heparin treatment

BACKGROUND: Heparin is an important medication in the treatment of patients with unstable angina pectoris. We designed an observational study to compare the effects of standard heparin (SH) with low molecular weight heparin (LMWH) on vascular endothelial growth factor (VEGF) levels in patients undergoing coronary artery bypass grafting (CABG). METHODS: Thirty-two patients with unstable angina pectoris undergoing CABG were prospectively categorized into two groups according to the type of heparin administration before surgery. VEGF levels determined by enzyme linked immunosorbent assay (ELISA) were compared between the two groups' blood samples obtained before the surgery and pericardial fluid after pericardial opening. RESULTS: There was no difference in preoperative characteristics between the two groups. Serum VEGF levels were similar (P=0.3) in patients treated by SH (85+/-55 pg/ml) compared to those treated with LMWH (105+/-64 pg/ml). VEGF levels in the pericardial fluid were significantly raised (P<0.0001) in patients of LMWH group (36+/-13 pg/ml) compared to SH group (13+/-6 pg/ml). A good correlation was observed between VEGF in the serum and platelet count in both SH group (r=0.8) and LMWH group (r=0.7). CONCLUSIONS: Local response of the ischemic myocardium, as expressed by VEGF levels, differs in patients treated with SH compared to patients treated with LMWH. VEGF levels in pericardial fluid of patients receiving LMWH were 2-3-folds higher than patients in SH group.