肺动脉高压肺血管重建大鼠基质金属蛋白酶3基因表达

目的 探讨基质金属蛋白酶3（MMP－3）mRNA转录在肺动脉高压肺血管重建中的可能作用。方法 利用野百合碱（MCT）诱导的大鼠肺动脉高压埃,药右心导管介入测定大鼠肺动脉平均压,RT－PCR法检测不同时间点大鼠肺组织MMP－3mRNA表达水平以及比色法测定主肺动脉段羟脯氨酸含量。结果 实验第21d肺动脉压力已明显升高,以第28d为最高,而大鼠肺组织MMP－3mRNA表达水平以第7d最高,第14、21、28d依次逐渐下调,第21d已接近正常水平,而主肺动脉段羟脯氨酸含量第14d异常降低,以后随肺动脉压力的升高而升高。结论 MMP－3早期转录水平升高可能与肺血管基底膜降解有关,参与对肺血管重建的触发作用,实验后期转录水平下调可能是导致细胞外基质积聚的重要原因之一。     

低氧大鼠肺内血管内皮细胞生长因子表达与肺血管重建的关系

目的　了解低氧性肺动脉高压时肺内血管内皮生长因子 (VEGF)与肺血管重建的关系。方法　将 2 0只雄性 Wistar大鼠分为低氧性肺动脉高压组 (n=10 )和对照组 (n=10 )两组 ,肺动脉高压组以常压低氧建立大鼠肺动脉高压模型。以微导管法测定各组大鼠肺动脉压 ,采用免疫组织化学染色法检测模型大鼠肺内 VEGF的表达 ,对肺组织切片进行图象分析。结果　低氧 3周后 ,肺动脉高压组大鼠形成明显的肺动脉高压 ,肺小动脉壁细胞数增多 ,管壁增厚和管腔狭窄 ,管壁厚度占外径的百分比 (WT%)为 31.4%± 2 .6 %,管壁面积占血管总面积的百分比 (WA%)为 5 2 .8%± 3.4%,分别与正常对照组 16 .0 %± 1.8%和 2 8.7%± 2 .3%相比明显升高 (P<0 .0 1) ;肺小动脉内膜的 VEGF免疫阳性染色在低氧大鼠组为 2 .5 1± 0 .2 5 ,与正常对照组 1.2 7± 0 .15相比明显增强 (P<0 .0 1) ,低氧大鼠组 VEGF免疫阳性染色强度与 WT%和 WA%呈明显正相关 (r分别为 0 .792和 0 .785 ,P <0 .0 1)。结论　低氧所致 VEGF的合成增多在低氧性肺血管重建和肺动脉高压的发病过程中起一定的作用。     

低氧大鼠肺内酪氨酸激酶受体flk—1表达与肺血管重建

OBJECTIVE: To assess the role of tyrosine-kinase receptor flk-1 in the development of hypoxic pulmonary vascular remodeling. METHODS: We divided 20 male Wistar rats into two groups(control vs hypoxia) and exposed them to normoxic condition and isobaric hypoxia for 3 weeks respectively. The pulmonary artery pressure was measured by right cardiac catheterization. The expression of flk-1 in lung tissues was measured by immunohistochemical staining. Histologic sections of the lungs were examined by a computerized image analyser. RESULTS: In hypoxic rats, the pulmonary artery pressure was significantly raised to a higher level, P < 0.01; the cell number of vascular wall was significantly increased. The results also demonstrated that chronic hypoxia brought about the significant increment in thickness of wall with narrowing of lumen of pulmonary arterioles, and the increment in the percent of vascular wall thickness/vascular external diameter (WT%) and the percent of vascular wall area/total vascular area (WA%), P < 0.01. The positive staining of flk-1 in the wall of pulmonary arteriole of rats treated with hypoxia was significantly stronger than that of normal rats, P < 0.01. Positive correlations were seen between the increment of expression of flk-1 with WT% and WA% (r = 0.714, 0.738, P < 0.01). CONCLUSION: Chronic hypoxia can induce an increasing expression of flk-1, and the flk-1 may play an important role in the pathogenesis of hypoxic pulmonary vascular remodeling.     

DDPH对肺动脉高压大鼠肺血管构形重建的影响

用测右心室收缩压（ＲＶＳＰ），右心室肥大指数（ＲＶＨＩ），Ｆｅｕｇｅｎ与弹力纤维复染，图像分析等方法，观测１－（２，６－二甲苯氧基）－２－（３，４－二甲氧基乙胺基）丙烷盐酸盐（ＤＤＰＨ）对野百合碱（Ｍ）诱发大鼠肺动脉高压和肺血管构形重建的影响，结果：（１）ＤＤＰＨ对Ｍ引起大鼠ＲＶＳＰ升高的抑制作用达３８．９５％，（２）ＲＶＨＩ和肺小动脉中膜厚度，Ｍ加ＤＤＰＨ（ＭＤ）组较Ｍ组分别低３３．４９％和４７     

慢性缺氧性小鼠肺血管结构重建模型的建立

建立一种新缺氧动物模型，为保健品抗缺氧实验提供新筛选方法。方法：选用初成年雄性昆明种小鼠，随机分为对照组和缺氧组。对照组动物在常压环境条件下喂养，缺氧组动物在常压缺氧舱中喂养。结果承缺氧时间延长，缺氧组ＭＡ、ＰＭＡ的比例较对照组明显增大，而ＮＭＡ的比例较对照组明显减少。     

低氧性肺血管重建与生长因子的关系

肺血管结构重建在低氧性肺动脉高压的发病机制中具有重要作用。前者的主要致病因子均可直接或间接改变生长因子的表达,从而促进肺血管平滑肌细胞增生肥厚,导致肺动脉高压发生。现就近年来对有关生长因子与低氧性肺动脉高压关系的研究作一综述。     

低氧大鼠肺内酪氨酸激酶受体flk-1表达与肺血管重建

目的　评价酪氨酸激酶受体 flk- 1在低氧性肺血管重建中的变化和作用。方法　以常压间断低氧建立大鼠肺动脉高压模型 ,以微导管法测定大鼠肺动脉压 ,采用免疫组织化学染色法检测模型大鼠肺内 flk- 1的表达 ,对肺组织切片进行图象分析。结果　低氧 3周后 ,大鼠形成明显的肺动脉高压、肺小动脉壁细胞数增多 ,以及管壁增厚和管腔狭窄 ,表现为管壁厚度占外径的百分比 (WT% )和管壁面积占血管总面积的百分比 (WA% )明显升高 (P<0 .0 1) ;肺小动脉内膜的 flk- 1免疫阳性染色在低氧大鼠组明显增强 (P<0 .0 1) ,与 WT%和 WA%呈明显正相关 (r分别为 0 .714和 0 .738,P<0 .0 1)。结论　慢性低氧介导 flk- 1表达增多 ,可能在低氧性肺血管重建和肺动脉高压的发病过程中起一定的作用     

室间隔缺损合并肺动脉高压的肺血管结构重建特点

目的 探讨室间隔缺损合并肺动脉高压的肺血管结构重建,分析肺血管结构重建与血流动力学指标之间的关系。方法 电镜观察肺血管超微结构变化,测定肺小动脉中层厚度百分比。结果 肺血管改变为Ｈｅａｔｈ ＆ ＥｄｗａｒｄｓⅢ级组与Ⅰ级组之间ＰＭＴ差异有非常显著意义,〉Ⅲ级组与Ⅰ级组之间ＰＭＴ差异有显著意义,而在其他组别之间,差异无显著意义。结论室间隔缺损合并肺动脉高压肺血管结构重建过程中,肺血管的改变以肺小动脉     

低氧性肺血管重建与生长因子的关系

肺血管结构重建在低氧性肺动脉高压的发病机制中具有重要作用,前者的主要致病因子均可直接或间接改变生长因子的表达,从而促进肺血管平滑肌细胞增生肥厚,导致肺动脉高压发生。现就近年来对有关生长因子与低氧性肺动脉高压关系的研究作一综述。     

间质胶原酶及其抑制因子-1不平衡表达与肝纤维化的关系

目的观察实验性肝纤维化过程中间质胶原酶（MMP－13）及其组织金属蛋白酶抑制因子-1（TIMP－1）基因表达的不平衡性。方法建立CCl4中毒性大鼠肝纤维化模型,采用SABC免疫组化方法和逆转录定量PCR方法测定MMP-13和TIMP－1的表达情况。结果MMP-13和TIMP－1在正常大鼠肝组织中有表达,在肝纤维化发生发展过程中MMP-13表达无显著性变化,而TIMP－1的表达则逐渐增强,在肝硬化阶段达到最高值。结论MMP-13和TIMP-1在肝纤维化过程中的不平衡表达可能是肝硬化形成的重要决定因素。     

与血管性痴呆大鼠学习记忆力相关的基因表达变化

血管性痴呆（vascular dementia,VD）是由各种脑血管因素（缺血或出血及急慢性缺氧性脑血管病）导致脑组织损害而引起的获得性智能损害综合征,以记忆、认知功能缺损为主,可伴有语言、视空间技能及人格障碍。近年来VD的发病率及病死率逐年上升,在世界范围内已成为继心脏病、癌症之后处第3位的致死性疾病。随着社会的进步和科技的发展,人类的平均寿命提高,人口老龄化已经成为全世界面临的重大社会和医学问题,严重威胁老年人的生命和生存质量,而且中国的VD发病呈逐年上升的趋势。近年来,诸多学者对VD对于记忆能力的影响做了各方面的研究,主要对与VD大鼠记忆力相关的凋亡相关基因、蛋白类、相关因子类等进行综述。     

薯蓣皂苷元对肺动脉高压大鼠肺血管重构的影响

目的：探讨薯蓣皂苷元（Dio）对野百合碱（MCT）诱导的肺动脉高压大鼠肺血管重构的影响。方法：将30只雄性 SD 大鼠随机分为正常对照组、MCT 组和 Dio 组,每组10只。MCT 组和 Dio 组一次性腹腔注射野百合碱60 mg/kg,建立大鼠肺动脉高压模型。Dio 组每天给予 Dio 80mg/kg 灌胃,对照组和 MCT 组给予相同量溶剂灌胃。待药物干预满4周后,分别测量各组干预后平均肺动脉压力（mPAP）、右心室肥大指数（RVHI）、肺小动脉管壁厚度占管径的百分比（WT％）和管壁面积占血管总面积的百分比（WA％）;采用免疫组化检测肺组织核因子-κB（NF-κB）的表达。结果：MCT 组的 mPAP、RVHI、WT％、WA％及 NF-κB 的表达水平均显著高于对照组和 Dio 组;经薯蓣皂苷元干预后,mPAP、RVHI、WT％、WA％及 NF-κB 的表达水平均明显降低。结论：薯蓣皂苷元能够缓解 MCT诱导的肺动脉高压大鼠肺血管重构,其机制可能与抑制 NF-κB 的表达有关。     

紫杉醇脂质体对肺动脉高压大鼠肺血管重构的干预作用

目的 探讨紫杉醇脂质体对野百合碱（monocrotaline,MCT）诱导肺动脉高压模型大鼠肺血管重构的影响。方法 将30只雄性Sprague–Dawley大鼠随机分为正常对照组（正常组）、野百合碱模型组（MCT组）和紫杉醇脂质体组（治疗组）,每组各10只;MCT组和治疗组大鼠腹腔注射1%MCT溶液造模,造模第21天起,治疗组大鼠予尾静脉注射紫杉醇脂质体,正常组和MCT组大鼠予尾静脉注射等量生理盐水,每3d注射1次,35d后测定各组大鼠右心室收缩压（right ventricular systolic pressure,RVSP）和右心室肥厚指数（right ventricular hypertrophy index,RVHI）;观察肺组织病理形态并检测肺动脉中膜厚度百分比、血管壁面积指数、增殖细胞核抗原（proliferating cell nuclear antigen,PCNA）及α–平滑肌肌动蛋白（α–smooth muscle actin,α–SMA）表达水平。结果 MCT组大鼠的RVSP、RVHI、肺动脉中膜厚度百分比、血管壁面积指数、PCNA及α–SMA表达均显著高于正常组（P<0.05）,治疗组大鼠的RVSP、RVHI、肺动脉中膜厚度百分比、血管壁面积指数、PCNA及α–SMA表达均显著低于MCT组（P<0.05）。结论 紫杉醇脂质体可降低MCT诱导肺动脉高压大鼠的肺动脉压力,缓解肺血管重构。     

Gene Expression Profile of Pulmonary Tissues in Different Phases of Lung Ischemia-reperfusion Injury in Rats

In order to provide us new clues to induce some endogenous protective molecular mechanisms, the changes in gene expression profile induced by ischemia-reperfusion in pulmonary tissues of rats were investigated and the dynamic mechanism of pulmonary ischemia-reperfusion injury was elucidated. Thirty male Wistar rats were randomly divided into 6 groups： 5 ischemia-reperfusion （I/R） groups （I/R 0-h, I/R 1-h, I/R 3-h, I/R 6-h, I/R 24-h） and control group （n=5 in each）. An in situ ischemia-reperfusion lung injury rat model was established by occluded hilus of lung. The RatRef-12 Expression Beadchip （22 226 gene probes per array） was used to analyze the pattern of gene expression in all groups. The results showed that 648, 340, 711, 1279 and 641 genes were differentially expressed in I/R 0-, 1-, 3-, 6- and 24-h groups respectively. The differentially expressed genes were classified as following 7 functional categories： cytokine, adhesion molecule, growth factor and apoptosis-related factor, oxidation and antioxidation molecule, metabolic enzyme, ion channel and aquaporin, signal transduction molecule. It was suggested that gene chip technology was an effective and quick method for screening differentially expressed genes. Many differentially expressed genes with different functions interacted each other to result in pulmonary ischemia-reperfusion injury.     

低氧肺动脉高压时血红素氧合酶基因表达状况的研究

目的 探讨血红素氧合酶(heme oxygenase,HO)基因在低氧肺动脉高压大鼠肺动脉组织中的表达及一氧化碳(carbon monoxide,CO)对其的影响.方法 60只Wistar大鼠随机分为5组:常氧组;低氧肺动脉高压组;血晶素组;锡原卟啉组;低浓度CO组(n=12).采用紫外分光光度计、逆转录-聚合酶链反应、免疫组织化学染色和原位杂交进行检测.结果 ①HO-1活性:低氧组、血晶素组、低浓度CO组肺动脉组织HO-1活性以胆红素生成量计算,均升高,其中血晶素组最高,与正常对照组比较,差异有显著性(P<0.01).②逆转录-聚合酶链反应:各组大鼠肺动脉HO-2 mRNA表达没有明显变化,均保持稳定.缺氧组、血晶素组、锡原卟啉组和低浓CO组HO-1 mRNA均明显高于正常对照组,以低浓度CO组升高最明显(P<0.01).血晶素组和低浓度CO组均显著高于缺氧组(P<0.01),而锡原卟啉组低于缺氧组.③免疫组织化学染色:低氧组肺动脉内膜、中膜的HO-1表达均明显升高,血晶素组和低浓度CO组更高,锡原卟啉组和常氧组均有很微弱表达.④原位杂交:低氧组肺动脉3层均加深2～3级,低浓度CO组肺动脉外、中、内膜细胞质均明显加深4级.处理前后HO-2的染色变化不大.结论 低氧肺动脉高压时,肺动脉组织HO-1基因的表达升高,可能在肺动脉高压的发生和发展中起一定作用. mRNA均明显高于正常对照组,以低浓度CO组升高最明显(P<0.01).血晶素组和低浓度CO组均显著高于缺氧组(P<0.01),而锡原卟啉组低于缺氧组.③免疫组织化学染色:低氧组肺动脉内膜、中膜的HO-1表达均明显升高,血晶素组和低浓度CO组更高,锡原卟啉组和常氧组均有很微弱表达.④原位杂交:低氧组肺动脉3层均加深2～3级,低浓度CO组肺动脉外、中、内膜细胞质 明显加深4级.处理前后HO-2的染色变化不大.结论 低氧肺动脉高压时,肺动脉组织HO-1基因的表达升高,可能在肺动脉高压的发生和发展中起一定作用. mRNA均明显高于正常对照组,以低浓度CO组升高最明显(P<0.01).血晶素组和低浓度CO组均显著高于缺氧组(P<0.01),而锡原卟啉组低于缺氧组.③免疫组织化学染色:低氧组肺动脉内膜、中膜的HO-1表达均明显升高,血晶素组和低浓度CO组更高,锡原卟啉组和常氧组均有很微弱表达.④原位杂交:低氧组肺动脉3层均加     

Mesenchymal stem cells attenuate vascular remodeling in monocrotaline-induced pulmonary hypertension rats

Intravenous and intratracheal implantation of mesenchymal stem cells (MSCs) may offer ameliorating effects on pulmonary hypertension (PH) induced by monocrotaline (MCT) in rats. The aim of this study was to examine the anti-remodeling effect of intravenous MSCs (VMSCs) and intratracheal MSCs (TMSCs) in rats with PH, and the underlying mechanisms. MSCs were isolated from rat bone marrow and cultured. PH was induced in rats by intraperitoneal injection of MCT. One week after MCT administration, the rats were divided into 3 groups in terms of different treatments: VMSCs group (intravenous injection of MSCs), TMSCs group (intratracheal injection of MSCs), PH group (no treatment given). Those receiving saline instead of MCT served as negative control (control group). Pulmonary arterial structure was pathologically observed, pulmonary arterial dynamics measured, and remodeling-associated cytokines Smad2 and Smad3 detected in the lungs, three weeks after MCT injection. The results showed that PH group versus control group had higher pulmonary arterial pressure (PAP) and wall thickness index (WTI) 21 days after MCT treatment. The expression of phosphorylated (p)-Smad2 and the ratio of p-Smad2/Smad2 were much higher in PH group than in control group. Fluorescence-labeled MSCs were extensively distributed in rats’ lungs in VMSCs and TMSCs groups 3 and 14 days after transplantation, but not found in the media of the pulmonary artery. WTI and PAP were significantly lower in both VMSCs and TMSCs groups than in PH group three weeks after MCT injection. The p-Smad2 expression and the ratio of p-Smad2/Smad2 were obviously reduced in VMSCs and TMSCs groups as compared with those in PH group. In conclusion, both intravenous and intratracheal transplantation of MSCs can attenuate PAP and pulmonary artery remodeling in MCT-induced PH rats, which may be associated with the early suppression of Smad2 phosphorylation via paracrine pathways.     

All-trans retinoic acid in pulmonary vascular structural remodeling in rats with pulmonary hypertension induced by monocrotaline

Objective To determine whether all-trans retinoic acid (atRA) exerts an inhibitory effect on rats with pulmonary hypertension induced by monocrotaline.Methods All rats were given a single subcutaneous injection of either monocrotaline (60 mg/kg) or saline.Monocrotaline-injected rats received either atRA (30 mg· kg(-1)·day(-1)) or saline through oral-gastro intubation.On Days 7 , 14, 21, and 28 respectively after monocrotaline injection, cardiovascular cath eters were inserted to examine the mean pulmonary artery pressure of rats in eac h group.Meanwhile, the matrix metalloproteinase-1 (MMP-1) mRNA expression an d hydroxyproline content in the main pulmonary artery were determined by RT-PCR and chromometry, respectively.Results The mean pulmonary artery pressure of rats in the model group increased signific antly on day 21 and reached a peak on Day 28 compared with the control group (25 .7±4.3 mm Hg vs 15.1±1.5 mm Hg and 38.5±6.4 mm Hg vs 16.4±2.0 mm Hg, P&lt;0.01).MMP-1 mRNA overexpression was present on Day 14 (0.72 ±0.15 vs 0.39±0.08, P&lt;0.01) and was rapidly down-regulated on Day 21 and 28 compared with Day 14, but was still higher than that in the control.The hydroxyoroline content of the main pulmonary artery dropped significantly on Da y 14 (4.01±1.13 μg/mg vs 5.10±0.91 μg/mg, P&lt;0.05) and increased s ignificantly on Days 21 and 28 compared with the control.atRA inhibited the MM P-1 mRNA overexpression from Day 14 to Day 28 and reduced the hydroxyproline co ntent (5.59±0.70 μg/mg vs 7.96±1.13 μg/mg and 7.77±0.96 μg/mg vs 9.93±1.27 μg/mg, P&lt;0.01) and the mean pulmonary artery pressure compa red with the model group (19.6±3.2 mm Hg vs 25.7±4.3 mm Hg and 26.3± 4.6 mm Hg vs 38.5±6.4 mm Hg, P&lt;0.01).Conclusion atRA inhibits MMP-1 overexpression and the accumulation of collagen, which migh t elicit favorable geometric remodeling in rat pulmonary hypertension induced by monocrotaline.     

基质金属蛋白酶在慢性低氧高二氧化碳大鼠肺血管重建中的作用

目的 :研究基质金属蛋白酶在低氧高二氧化碳大鼠肺血管重建中的作用。方法 :将SD大鼠分为正常对照组 (C组 ) ,3w低氧高二氧化碳组 (H组 )。采用光镜、图像分析、免疫杂交等方法 ,观察各组大鼠肺动脉平均压 (mPAP)、颈动脉平均压 (mCAP)、右心室 / (左心室 室间隔 )重量比RV/ (LV S)、肺细小动脉显微结构、肺组织羟脯氨酸含量及明胶酶A、B(MMP 2、MMP 9)的表达变化。结果 :①H组mPAP、RV/LV S显著高于C组 (P <0 .0 1)。②肺组织匀浆羟脯氨酸含量H组显著高于C组 (P <0 .0 1)。③光镜下肺细小动脉管壁面积 /管总面积 (WA/TA)、管腔面积 /管总面积 (EA/TA)、肺细小动脉中膜厚度 (PAMT)C组明显低于H组 (P <0 .0 1)。④免疫杂交法检查发现肺组织匀浆MMP 2、MMP 9含量H组较C组显著升高 (P <0 .0 1)。结论 :低氧高二氧化碳促使基质金属蛋白酶表达升高 ,提示金属蛋白酶参与了肺血管重建