低氧对大鼠肺组织一氧化氮合酶分布及活性的影响

本研究利用低压缺氧性肺动脉高压大鼠模型，通过NADPH－d组织化学染色对肺组织一氧化氮合酶（NOS）进行定性及定位分析、并利用3H－L一精氨酸转化实验定量测定肺组织NOS的活性，以观察低氧对大鼠肺组织NOS分布及活性的影响，旨在探讨NO及NOS在缺氧性肺动脉高压形成中的作用。酶活性测定结果表明缺氧2周大鼠肺组织总NOS活性略有升高，其中原生型NOS（CNOS）活性显著降低（P＜0．05），诱生型NOS（iNOS）活性极显著升高（P＜0．01），NADPH－d染色结果显示肺血管内皮及平滑肌细胞NOS活性均明显增强。提示缺氧可能使肺血管内皮CNOS活性降低，NO生成减少，从而导致肺血管收缩反应增强，肺动脉压升高；缺氧还可能诱导肺血管内皮和平滑肌细胞iNOS表达和活性增加，在缺氧性肺血管收缩反应和结构重组中起到一定的调节作用，从而限制肺动脉压的过度升高。     

一氧化氮对急、慢性缺氧大鼠血流动力学及缺氧性肺血管收缩反应的影响

观察了吸入０．００４％的一氧化氮（ＮＯ）对急、慢性缺氧大鼠血流动力学、缺氧性肺血管收缩反应（ＨＰＶ）、血气及高铁血红蛋白（ＭｅｔＨｂ）的影响。结果表明：（１）常氧吸入ＮＯ时能明显降低慢性缺氧大鼠肺动脉平均压（Ｐｐａ）和肺血管阻力（ＰＶＲ），但对正常大鼠的Ｐｐａ和ＰＶＲ无明显影响；（２）慢性缺氧大鼠急性缺氧时ＨＰＶ较正常大鼠弱，吸入ＮＯ不但降低两者的急性缺氧肺动脉高压，且完全逆转两者的ＨＰＶ；（３）吸入ＮＯ对急、慢性缺氧大鼠体循环血流动力学、血气及ＭｅｔＨｂ含量无明显影响。提示吸入ＮＯ能选择性降低，急、慢性缺氧性肺动脉高血压，且逆转ＨＰＶ。     

L—精氨酸对急性缺氧大鼠血浆NO和ET含量变化的影响

目的 为了研究外源性L-精氨酸（L-Arg）对急性缺氧大鼠血浆一氧化氮（NO）和内皮素（ET）含量变化的影响。方法 采用组织化学方法,生化Griess法和放射免疫法分别测定大鼠肺血管内膜一氧化氮合酶（NOS）活性,血浆NO、ET和环腺苷酸（cGMP）含量水平。结果 （1）急性缺氧1h后血浆NO和cGMP含量水平下降,血浆ET含量水平上升,肺血管内膜NOS活性下降。（2）L-Arg干预后血浆NO和cGMP 含量水平较缺氧组明显增加,血浆ET含量水平则明显下降,而局部肺血管内膜NOS活性较缺氧组无显著差异。结论 急性缺氧能导致血浆NO含量水平下降,血浆ET水平升高,肺血管内膜NOS活性下降。应用外源性L-Arg干预急性缺氧可使下降NO水平升高。血浆ET水平下降,从而推测L-Arg有缓解缺氧毒性及缓解性肺动脉高压的作用,故临床上运用L-Arg可望对某些疾病具有有益的治疗作用。     

Interrelation between nitric oxide and endothelin-1 in an experimental acute hypoxia in rats and its intervention

ＯｂｊｅｃｔｉｖｅｓＴｏｓｔｕｄｙｔｈｅｉｎｔｅｒｅｌａｔｉｏｎｂｅｔｗｅｅｎｎｉｔｒｉｃｏｘｉｄｅ（ＮＯ）ａｎｄｅｎｄｏｔｈｅｌｉｎ１（ＥＴ１）ｉｎｅｘｐｅｒｉｍｅｎｔａｌａｃｕｔｅｈｙｐｏｘｉｃｒａｔｓ,ａｎｄｔｏｅｖａｌｕａｔｅｔｈｅｍｅｃｈ...     

缺氧性肺动脉高压大鼠肺动脉一氧化氮合酶的实验研究

目的：研究大鼠肺动脉中一氧化氮合酶（ｎｉｔｒｉｃ ｏｘｉｄｅｓｙｎｔｈａｓｅ,ＮＯＳ）的含量及分布变化与慢性缺氧性肺动脉高压（ｈｙｐｏｘｉｃｐｕｌｍｏｎａｒｙ ｈｙｐｅｒｔｅｎｓｉｏｎ, ＨＰＨ）发生的关系。方法：采用ｅＮＯＳ多克隆抗体,对慢性ＨＰＨ 大鼠的肺组织进行免疫组织化学分析,观察缺氧组及对照组大鼠各级肺动脉中ｅＮＯＳ含量及定位;同时应用分光光度计测定缺氧组及对照组大鼠血浆中ＮＯ的间接浓度。结果：正常大鼠肺动脉内皮细胞及平滑肌细胞均含有较高的ｅＮＯＳ表达,且各级肺动脉中ｅＮＯＳ含量差异无显著性;缺氧组大鼠各级肺动脉内皮细胞及平滑肌细胞ｅＮＯＳ含量均较对照组显著减少;缺氧组大鼠血浆ＮＯ间接浓度较对照组明显降低。结论：大鼠肺动脉内皮细胞和平滑肌细胞ｅＮＯＳ含量下降及血浆ＮＯ浓度下降参与慢性ＨＰＨ 的形成。     

灯盏花素对大鼠低氧性肺动脉高压治疗作用及血清一氧化氮和内皮素-1的影响

为探讨灯盏花素对大鼠慢性低氧性肺动脉高压的治疗作用及机制,应用灯盏花素腹腔注射,观察其对大鼠不同低氧时间肺动脉平均压(mPAP)、血清一氧化氮（Nitricoxide,NO）及内皮素-1（Endothelin-1,ET-1）含量的影响,并与单纯低氧组对照。结果显示单纯低氧组大鼠mPAP和血清内皮素-1含量在低氧5、14和28d均明显增高（P<0.01）,血清一氧化氮明显降低（P<0.01）;灯盏花素治疗组肺动脉平均压和血清内皮素-1含量在低氧5、14和28d均较单纯低氧组明显降低（P<0.01）,血清一氧化氮含量明显升高（P<0.01）。灯盏花素明显降低大鼠慢性低氧性肺动脉高压,可能是通过增加血清NO、降低ET-1含量发挥其作用的,可用于慢性肺动脉高压的治疗。     

慢性阻塞性肺疾病并发肺动脉高压、肺心病患者血浆脂肪炎症因子、一氧化氮、一氧化氮合成酶水平及临床意义的探讨

目的测定慢性阻塞性肺疾病、肺动脉高压、慢性肺源性心脏病(肺心病)患者外周血脂肪炎症因子(apelin)、一氧化氮(NO)、一氧化氮合成酶(NOS)水平,探讨apelin、NO、NOS之间的关系及与慢性阻塞性肺疾病所致肺动脉高压、肺心病的关系,揭示apelin的生物学作用、在肺动脉高压和肺心病发生发展中的意义。方法 2008年10月—2010年6月我科随访的慢性阻塞性肺疾病稳定期患者60例,其中慢性阻塞性肺疾病并发肺动脉高压、肺心病出现心力衰竭患者(心衰组)18例,慢性阻塞性肺疾病并发肺动脉高压、肺心病未出现心力衰竭患者(肺动脉高压组)20例,慢性阻塞性肺疾病无肺动脉高压、肺心病患者(COPD组)22例。选取同期健康体检正常者20例为对照组。应用酶联先疫吸附法(ELISA)检测4组受检者血浆apelin、NO、NOS水平。结果 4组受检者血浆apelin、NO、NOS水平比较,差异均有统计学意义(P<0.01)。其中COPD组apelin、NO、NOS水平与对照组比较,差异均无统计学意义(P>0.05);肺动脉高压组apelin、NO、NOS水平与对照组、COPD组比较,差异均有统计学意义(P<0.05);心衰...     

大鼠肺内NOS之分布及缺氧对其活性的影响

本文以组织化学方法对大鼠肺内一氧化氮合成酶（ＮＯＳ）进行定位研究，并观察了不同时间（８小时～２８天）缺氧时肺内ＮＯＳ活性的变化。结果显示：①正常大鼠各级支气管、肺泡管和肺泡囊上皮细胞呈ＮＯＳ强阳性反应；肺血管内膜呈ＮＯＳ阳性反应。②缺氧８小时，肺血管内膜ＮＯＳ阳性反应开始降低，且缺氧时间越长，ＮＯＳ阳性反应越低。③缺氧１４天时，肺泡间质和肺血管周围炎性细胞呈ＮＯＳ阳性反应；缺氧２８天时，炎性细胞ＮＯＳ阳性反应增强。④缺氧对支气管、肺泡管和肺泡囊上皮细胞ＮＯＳ的活性无明显影响。从而提示一氧化氮不仅对肺具有一定的生理学作用，而且可能参与缺氧时肺的某些病理学过程。     

缺氧性肺动脉高压大鼠肺iNOS表达的实验研究

目的　观察慢性缺氧大鼠肺组织诱生型一氧化氮合酶 (iNOS)表达的变化 ,并探讨iNOS在肺动脉高压发病中的作用。　方法　运用血清学检验及免疫组织化学方法观察血一氧化氮 (NO)、肺组织iNOS蛋白表达的变化。　结果　正常组大鼠iNOS表达呈弱阳性 ,慢性缺氧后肺组织iNOS蛋白表达呈强阳性 ,血一氧化氮水平升高 (P <0 0 1 )。　结论　一氧化氮合酶表达增强及一氧化氮参与慢性缺氧性肺动脉高压发病过程 ,诱生型一氧化氮合酶的表达及一氧化氮的血管舒张作用与氧自由基作用的放大效应可能是肺动脉高压形成的重要因素     

内源性一氧化氮与硫化氢在大鼠低氧性肺动脉高压中的相互作用

目的:研究一氧化氮(nitric oxide,NO)/一氧化氮合酶(nitric oxygnase, NOS)体系和硫化氢(hydrogen sulfide,H2S)/胱硫醚γ-裂解酶(cystathionine-γ-lyase,CSE)体系在低氧性肺动脉高压发生机制中的作用及其相互关系.方法:将25只大鼠随机分为4组:低氧组(7只)、低氧 L-NAME组(给与NOS抑制剂Nω-硝基-L-精氨酸甲酯处理的低氧组,6只)、低氧 PPG组(给与CSE抑制剂炔丙基甘氨酸处理的低氧组,6只)和对照组(6只).低氧21 d后,测定肺动脉平均压、血浆NO及H2S含量,分别测定低氧组、低氧 L-NAME组及对照组CSE活性,应用免疫组织化学的方法检测低氧组、低氧 PPG组及对照组的肺动脉内皮细胞eNOS表达.结果:低氧21 d大鼠肺动脉平均压力明显增高,同时血浆中NO和H2S含量、肺动脉内皮细胞eNOS表达及肺组织CSE活性亦明显下降;而低氧 L-NAME组,伴随着NO含量的下降,肺动脉平均压显著上升,同时,血浆中的H2S含量及肺组织CSE活性较低氧组显著上升;在低氧 PPG组,伴随血浆H2S含量的降低,肺动脉压力显著升高,同时血浆中的NO含量及肺血管内皮细胞eNOS表达也较低氧组显著上升.结论:内源性NO/NOS体系与H2S/CSE体系在低氧性肺动脉高压中呈现相互的负性调节作用.它们既相互独立又以网络调节的方式共同参与低氧性肺动脉高压形成的调控机制.     

Effects of Salvia miltiorrhiza extracts on rat hypoxic pulmonary hypertension, heme oxygenase-1 and nitric oxide synthase

Objective To investigate the effects of Salvia miltiorrhiza (SM) extracts on the expression of heme oxygenase-1 (HO-1) and nitric oxide synthase (NOS) in small pulmonary arteries (SPAs) of rats with chronic hypoxia.Methods After two weeks of hypoxia, rats were treated with diltiazem, and small, median, and large doses of SM extracts. The lungs were tested for the expression and distribution of HO-1, endothelial NOS (eNOS) and inducible NOS (iNOS) by using immunohistochemistry and Western blot method.Results Median and large doses of SM extracts significantly reduced hypoxia-induced media thickening in the SPAs (similar with diltiazem), recovered repaired ultrastructure injury, decreased HO-1 and iNOS levels, and increased eNOS expression in the SPAs.Conclusions Median and large doses of SM extracts play significant roles in inhibiting structural remodeling in rats with hypoxic pulmonary hypertension. These effects might attribute to the suppression of HO-1 and iNOS, and the promotion of eNOS expression under the conditions of hypoxia.     

尼群地平与硝苯吡啶及克普定和L-精氨酸对大鼠低氧性肺动脉高压的影响比较

观察了Ca通道拮抗剂：尼群地平（Nit），硝苯吡啶（Nif）和内皮依赖性血管舒张因子（EDRF）合成前质L－精氨酸（L－A）对大鼠慢性低氧肺动脉高压、右心室肥厚和肺血管肌化的影响，以及血管紧张素转换酶抑制剂克普定（Cap）、L－A与钙通道拮抗剂联合使用的效果。结果发现：Nit，Nif与L－A，都能影响低氧性慢性肺动脉高压形成和减轻缺氧引起的右室肥大。CaP可以增强Nit的作用，各用药组中以Nit合并Cap在降低肺动脉高压、右室压和抑制肺小动脉肌化方面效果最好（P＜0．05）。     

Effects of Salvia miltiorrhiza extracts on rat hypoxic pulmonary

Objective To investigate the effects of Salvia miltiorrhiza (SM) extracts on the expression of heme oxygenase-1 (HO-1) and nitric oxide synthase (NOS) in small pulmonary arteries (SPAs) of rats with chronic hypoxia.
Methods After two weeks of hypoxia, rats were treated with diltiazem, then small, medium, and large doses of SM extracts. The lungs were tested for the expression and distribution of HO-1, endothelial NOS (eNOS) and inducible NOS (iNOS) by using immunohistochemistry and Western blot method.
Results Median and large doses of SM extracts significantly reduced hypoxia-induced media thickening in the SPA (similar with diltiazem), recovered repaired ultrastructure injury, decreased HO-1 and iNOS levels, and increased eNOS expression in the SPA.
Conclusions Median and large doses of SM extracts play significant roles in inhibiting structural remodeling in rats with hypoxic pulmonary hypertension. These effects might attribute to the suppression of HO-1 and iNOS, and the promotion of eNOS expression under the conditions of hypoxia.     

Inhibition of Expression of Hypoxia-inducible Factor-1αmrna by Nitric Oxide in Hypoxic Pulmonary Hypertension Rats

Summary: In order to study the effect of nitric oxide (NO) on the expression of hypoxia-inducible factor-1 alpha (HIF-la) mRNA in hypoxic pulmonary hypertension (HPH) rats, 30 healthy male Wistar rats were randomly divided into normoxic control group, chronic hypoxic group and hypoxia plus L-argine (L-Arg) group. The animal model of HPH was developed. The mean pulmonary arterial pressure (mPAP) was measured by inserting a microcatheter into the pulmonary artery. The HIF-1α mRNA expression levels were detected by in situ hybridization (ISH) and semiquantitative RT-PCR. It was found that after 14 days hypoxia, the mPAP in normoxic control group (17.6±2. 7 mmHg,1 mmHg=0. 133 kPa) was significantly lower than that in chronic hypoxic group(35.8±6.1 mmHg, t=0. 2918, P＜0.05) and mPAP in chronic hypoxic group was higher than that in hypoxia plus L-argine group(24.4±3.8 mmHg, t==0. 2563, P＜0. 05). ISH showed that the expression of HIF-lα mRNA in the intraacinar pulmonary arteriolae (IAPA) in normoxic control group (0. 1076±0. 0205) was markedly weaker than that in chronic hypoxic group (0. 3317 ± 0.0683, t=3. 125, P＜0. 05) and that in chronic hypoxic group was stronger than that in hypoxia plus L-argine group (0. 1928±0. 0381, t=2.844, P＜0.05). RT-PCR showed that the content of HIF-lα mRNA in chronic hypoxic group (2. 5395±0. 6449) was 2.16 times and 1.75 times higher than that in normoxic control group (1. 1781±0. 3628) and hypoxia plus L-argine group (1. 4511±0. 3981), respectively. It is concluded that NO can reduce the mPAP by the inhibition of the expression of HIF-1α mRNA, which may be one of the mechanisms through which NO affects the pathogenesis of HPH.     

瓜蒌薤白半夏汤制剂对缺氧性肺动脉高压血NO、PAF的影响

探讨一氧化氮 (NO)、血小板激活因子 (PAF)与缺氧性肺动脉高压的关系及瓜蒌薤白半夏汤的作用机理 ,观察了常压缺氧性肺动脉高压时NO、PAF和肺血管形态变化及瓜蒌薤白半夏汤对其的影响。结果表明 :在大鼠常压缺氧性肺动脉高压时 ,血浆中NO水平降低、PAF的含量升高 (P <0 0 1 ) ,瓜蒌薤白半夏汤能明显升高NO和降低PAF的含量 (P <0 0 1 ) ,且大鼠肺小动脉管壁增厚、管腔狭窄程度显著减轻。     

ET－1和NO对肺动脉平滑肌细胞DNA合成的作用及缺氧对其调制的研究

观察内皮素－１（ＥＴ－１）和一氧化氮（ＮＯ）在缺氧性肺血管结构重组中的作用，发现ＥＴ－１可促进肺动脉平滑肌细胞（ＰＡＳＭＣ）ＤＮＡ合成，其促进作用呈剂量依赖性；ＮＯ供应剂ＳＮＰ则起抑制作用，ＮＯ的抑制增殖作用主要由ｃＧＭＰ介导。在此基础上观察到缺氧可促进ＰＡＳＭＣ对ＥＴ－１的增殖反应，同时可抑制ＰＡＳＭＣ胞浆内可溶性鸟苷酸环化酶活性而降低ＰＡＳＭＣ对ＮＯ等舒血管药物的反应性。提示ＥＴ－１和ＮＯ及缺氧在缺氧性肺血管结构重组中具有重要的作用。     

血管内皮生长因子在低氧性肺动脉高压大鼠肺内的分布和水 …

This study was designed to elucidate whether the level and distribution of vascular endothelial growth factor (VEGF) are changed in the lungs of rats with hypoxic pulmonary hypertension. 13 male Wistar rats were exposed to isobaric hypoxia for 3 weeks. The pulmonary artery pressure was measured by right cardiac catheterization. The level of VEGF in pulmonary homogenate was measured by Elisa method. The distribution of VEGF in the rat lung was examined by immunohistochemistry. The results showed that the pulmonary artery pressure was significantly increased after hypoxic exposure. The level of VEGF in pulmonary homogenate of rats treated with hypoxia (466.9 +/- 75.5 pg/g) were significantly increased as compared with taht of normal rats (376.2 +/- 47.1 pg/g). The contents of VEGF in the wall of pulmonary arteriole were significantly increased in rats with pulmonary hypertension. So we suggest that chronic hypoxia can strongly stimulate VEGF secretion, and VEGF may mediate the process of hypoxic pulmonary vascular remodeling and pulmonary hypertension.     

天龙咳喘灵胶囊防治大鼠慢性低氧性肺动脉高压的NO机制

目的:探讨天龙咳喘灵胶囊(TLC)防治大鼠慢性常压低氧性肺动脉高压的NO机制。方法:SD大鼠随机分为:正常对照组、单纯低氧组和低氧 TLC组,除正常对照组外其余两组置于常压低氧舱内饲养,10h/d,共28d,然后测定各组大鼠平均肺动脉压(mPAP)和动脉血中NO含量及NOS活性,并分析平均肺动脉压和NO含量的相关性。结果:与正常对照组相比,低氧组大鼠mPAP显著升高;TLC干预后能显著抑制低氧所致的mPAP升高,与正常对照组比较无显著性差异。慢性低氧使大鼠动脉血中NO含量和NOS活性显著降低,而低氧 TLC组与正常对照组相比,NO含量和NOS活性均无显著性差异。相关分析显示,mPAP与血浆NO含量之间呈负相关(r=0.745)。结论:TLC可通过增加NO含量,抑制大鼠慢性低氧性肺动脉高压的形成。