P2X7R在肺动脉高压患者及人肺动脉内皮细胞中的表达

目的探讨肺动脉高压患者与人肺动脉内皮细胞中P2X7受体(P2X7R)的表达变化,探讨P2X7R是否参与肺动脉高压发病。方法人的肺组织来源于黑龙江省医院,其中对照组取自右下肺叶球形性变实施肺叶切除患者的肺组织,病变组取自患有特发性肺动脉高压尸检患者的肺组织,应用免疫印迹及实时定量PCR技术检测P2X7R的表达变化。人肺动脉内皮细胞系给予缺氧处理后,采用免疫印记技术检测P2X7R的表达变化。结果原发性肺动脉高压患者肺组织P2X7R在蛋白及m RNA水平的表达均较对照组明显增高。缺氧组肺动脉内皮细胞P2X7R在蛋白水平的表达较常氧对照组明显增高。结论原发性肺动脉高压患者肺组织及缺氧肺动脉内皮细胞P2X7R表达上调,提示P2X7R可能参与肺动脉高压发病过程。     

肺动脉高压患者肺组织S1PR1/2/3的表达

目的探讨肺动脉高压患者肺组织1-磷酸鞘氨醇受体1/2/3(sphingosine-1-phosphate receptor1/2/3,S1PR1/2/3)的表达变化,为肺动脉高压发病机制的深入研究奠定基础。方法人的肺组织来源于黑龙江省医院,其中对照组取自右下肺叶球形性变实施肺叶切除患者的肺组织,病变组取自患有特发性肺动脉高压尸检患者的肺组织,应用免疫印迹及实时定量PCR技术检测S1PR1/2/3的表达变化。结果原发性肺动脉高压患者肺组织S1PR1/2/3蛋白的光密度值分别为2.00±0.03,0.86±0.13,0.94±0.03,m RNA的绝对定量值分别为3.90±0.42,2.50±0.37,92.08±11.26,较对照组蛋白的光密度值(0.88±0.29,0.27±0.07,0.54±0.06)及m RNA的绝对定量值(1.44±0.33,1.12±0.15,1.63±0.56)明显增高(P0.01)。结论原发性肺动脉高压患者肺组织S1PR1/2/3的表达上调,提示S1PR1/2/3在肺动脉高压发病过程中可能发挥了重要的作用。     

慢性低氧性肺动脉高压大鼠肺内肺动脉中尾加压素Ⅱ的变化

本实验旨在研究尾加压素Ⅱ（uⅡ）在慢性低氧性肺动脉高压及肺血管结构重构形成中的变化。应用免疫组化技术对慢性低氧性肺动脉高压大鼠不同节段肺内动脉uⅡ蛋白表达进行定位及半定量分析。结果显示：低氧1周和2周组大鼠肺动脉平均压（mPAP）、右心室肥厚指标R／（L＋S）、肺动脉相对中膜面积（RMA）和相对中膜厚度（RMT）均明显高于对照组（P＜0.001）。低氧2周组大鼠各节段肺内动脉内皮细胞中uⅡ表达较对照组分别下降27.75%、32.50%、39.63%（P均＜0.01）。相关分析显示：与呼吸性细支气管伴行的肺动脉内皮细胞uⅡ表达与mPAP呈显著负相关；各节段肺动脉内皮细胞uⅡ表达分别与各级肺动脉RMA、RMT呈明显负相关（P均＜0.05）。研究表明：低氧性肺动脉高压及肺血管结构重构形成过程中，肺内动脉内皮细胞uⅡ表达呈现明显下调；推测uⅡ在慢性低氧性肺动脉高压形成机制中具有重要的病理生理意义。     

高碳酸血症通过赖氨酰氧化酶依赖的胶原蛋白交联影响大鼠缺氧性肺动脉高压

目的:通过研究缺氧和/或高碳酸血症时赖氨酰氧化酶(LOX)以及细胞外基质胶原蛋白的交联变化,探讨高碳酸血症对缺氧性肺动脉高压的影响机制。方法:SD大鼠随机均分为4组,分别为常氧对照组、缺氧组、高碳酸血症组以及缺氧+高碳酸血症组。比色法测定胶原蛋白含量,荧光光谱法分析LOX酶活性,免疫组织化学和Western blot法检测肺动脉LOX蛋白含量,实时荧光定量PCR检测肺动脉LOX的mRNA水平。结果:缺氧组大鼠平均肺动脉压(m PAP)、右心室/(左心室+室间隔)重量比值[RV/(LV+S)]及血管壁面积(WA)/血管总面积(TA)均明显高于常氧对照组;高碳酸血症组与常氧对照组的m PAP、RV/(LV+S)差异无统计学显著性;缺氧+高碳酸血症组大鼠的m PAP及RV/(LV+S)显著低于单纯缺氧组。缺氧组大鼠肺组织的胶原交联程度则明显高于常氧组及高碳酸血症组;高碳酸血症组大鼠肺组织的胶原交联程度与常氧组比较无显著差异;缺氧+高碳酸血症组大鼠肺组织的胶原交联程度显著低于缺氧组。缺氧组大鼠肺动脉LOX的mRNA、蛋白表达量及其酶活性均高于常氧组(P0.01);缺氧+高碳酸血症组大鼠肺动脉LOX mRNA、蛋白表达以及酶活性均明显低于缺氧组(P0.01)。结论:缺氧能诱导肺动脉LOX高表达,通过促进胶原合成及交联,参与肺动脉高压的形成。高碳酸血症通过抑制缺氧诱导的LOX表达和胶原交联,延缓缺氧性肺动脉高压的进展。     

慢性低氧性肺动脉高压大鼠肺组织P53表达增高

目的观察P53在低氧性肺动脉高压大鼠肺组织中的表达。方法采用减压低氧方法复制大鼠慢性低氧性肺动脉高压模型;取肺组织,常规SABC免疫组化法染色和Hoechst染色,观察P53表达的变化及细胞凋亡变化。结果P53在慢性肺动脉高压大鼠肺小动脉壁中有少量表达,其中低氧3周组>低氧2周组>正常组。Hoechst染色显示肺组织凋亡细胞增加,其变化趋势与P53的表达变化趋势相同。结论在慢性低氧性肺动脉高压形成过程中,肺小动脉壁发生了增殖和凋亡,程度随低氧时间的延长而增加,同时P53表达增多,提示P53参与了慢性低氧性肺动脉高压肺小血管重建的调控。     

缺氧对肺动脉成纤维细胞MMP-2、TIMP-1表达的影响

目的：探讨缺氧对肺动脉成纤维细胞（Fpa）分泌基质金属蛋白酶（MMPs）、金属蛋白酶组织抑制剂（TIMPs）的影响。 方法： 采用酶谱法测定Fpa培养基中MMP-2的酶活性，免疫印迹法检测培养基中MMP-2、TIMP-1 的蛋白水平，免疫组化法测定细胞原位的蛋白表达， RT-PCR法检测mRNA表达量。 结果： 缺氧后Fpa分泌的MMP-2酶活性、细胞内外蛋白表达量、mRNA表达量均下降；而TIMP-1的表达则呈相反变化。 结论： 缺氧可使肺动脉成纤维细胞MMP-2/TIMP-1的表达失衡，可能参与缺氧性肺血管重建。     

Gax在肺动脉高压大鼠肺动脉中的表达变化

目的:使用低氧及野百合碱(monocrotaline,MCT)诱导的两种肺动脉高压(pulmonary arterialhypertension,PAH)大鼠模型,观察生长终止特异性同源盒(growth arrest-specific homeobox,Gax)在肺动脉的表达变化。方法:Sprague Dawley大鼠随机分为四组:低氧模型组(n=16)、低氧对照组(n=16)、MCT模型组(n=16)及MCT对照组(n=16)。采用插管法测定大鼠的右心室压力及肺动脉压力。右心室质量除以左心室和室间隔质量,计算右心肥厚指数。采用定量RT-PCR法测定肺动脉主干及肺组织Gax mRNA表达;采用Western免疫印迹法测定肺动脉主干Gax蛋白表达;免疫组织化学染色观测Gax在肺内的分布及表达变化。结果:低氧模型组及MCT模型组大鼠的右心压力、肺动脉压力及右心肥厚指数均显著高于相应对照组(P<0.01),两种模型大鼠的肺动脉血管均出现明显重构。与对照组比较,Gax mRNA在两种模型组大鼠的肺组织表达降低(P<0.05),而在肺动脉主干表达升高(P<0.05)。Gax蛋白在肺内主要表达在微小动脉。与对照组比较,两种模型组大鼠的肺动脉主干和肺微小动脉Gax蛋白表达均升高(P<0.05),而肺组织Gax蛋白表达下降(P<0.05)。结论:Gax主要表达在肺微小动脉,在PAH发生时表达上调。     

低氧性肺动脉高压大鼠肺组织apelin-APJ系统的变化

目的探讨新发现的小分子活性肽apelin及其受体APJ与缺氧性肺动脉高压病理进程的关系及意义。方法清洁级雄性SD大鼠20只,随机分为正常对照组和低氧2周组。测定平均肺动脉压(mPAP)、平均颈动脉压(mCAP)及右心室与左心室+室间隔重量比(RV/LV+S),以评价缺氧性肺动脉高压模型。放免法测定血浆、肺组织匀浆apelin水平,免疫组织化学和RT-PCR分别检测肺组织apelin、APJ蛋白及基因表达的变化。结果①缺氧大鼠mPAP较对照组高124.88%(P<0.01),RV/LV+S较对照组高25.33%(P<0.01)。两组大鼠mCAP差异无统计学意义。②肺组织及血浆apelin浓度,缺氧组与对照组比较,分别为10.58±1.02vs11.17±0.73(pg/mg.pro)和479±45vs427±63(pg/ml),P均>0.05。免疫组化显示,缺氧大鼠肺组织APJ的表达较对照组低,而apelin的表达两者差异无显著性。③缺氧大鼠肺组织apelinmRNA表达水平与对照组比较差异无统计学意义(0.925±0.058vs1.021±0.036,P>0.05),而APJmRNA的表达显著低于后者(0.944±0.106vs1.199±0.053,P<0.05)。结论APJ受体表达的异常下调所致的apelin-APJ信号系统受损,在缺氧性肺动脉高压发生、发展过程中可能扮演重要角色。     

肝素抑制低氧性肺动脉高压大鼠肺血管内皮生长因子1的表达

目的： 观察肝素抑制大鼠低氧性肺动脉高压过程中,血管内皮生长因子1（VEGF-1）在肺小动脉血管内皮细胞和肺组织中的表达变化。方法：成年雄性SD大鼠24只,随机分为对照组（A组）、低氧4周组（B组）和低氧+肝素4周组（C组）,每组8只。测各组大鼠平均肺动脉压（mPAP）、右室肥大指数（RVHI）和血管形态学指标;HE染色观察肺动脉血管形态学改变,免疫组化法检测肺动脉血管内皮细胞VEGF-1蛋白表达;RT-PCR检测肺组织VEGF-1基因表达。结果：mPAP、RVHI、肺小动脉重塑指标、肺小动脉血管内皮细胞VEGF-1蛋白表达和肺组织VEGF-1基因表达水平在C组高于A组,低于B组。相关分析表明,VEGF-1蛋白表达与肺血管重塑呈正相关（r=0.974,P<0.01）。VEGF-1mRNA与VEGF-1蛋白呈正相关（VEGF120 mRNA,r=0.919, P<0.01;VEGF164 mRNA,r=0.896, P<0.01）。结论：肝素可能在转录和翻译水平抑制VEGF-1的表达,从而抑制大鼠低氧性肺动脉高压的形成。     

肺动脉高压大鼠T型和TC型肥大细胞的改变

目的:建立SD大鼠高肺血流并用野百合碱注射所致肺动脉高压模型,观察肺组织中肥大细胞及肥大细胞两种亚型的变化,探讨肥大细胞在肺动脉高压中的机制。方法:大鼠腹主动脉-下腔静脉造瘘,术后7天一次性腹腔注射野百合碱60mg/kg,制造肺动脉高压模型,35天后测定肺动脉压,取肺组织进行免疫组织化学染色,观察肥大细胞的变化,HE染色观察肺组织一般病理变化。结果:HE染色显示肺组织中动脉管壁明显增粗,有新生血管形成。平均肺动脉压力模型组较对照组升高(P<0.05);右心室/(左心室+室间隔)模型组较对照组增加(P<0.05),肥大细胞总数及类糜蛋白酶阳性的肥大细胞模型组较对照组增多(P<0.05)。结论:腹主动脉-下腔静脉造瘘合并野百合碱腹腔注射成功的建立了肺动脉高压的动物模型,肥大细胞在肺组织的聚集以及活化、肥大细胞亚型的改变可能是肺动脉高压形成的机制之一。     

肺部超声对重症肺部感染患者肺通气的评估价值

目的:探讨肺部超声评价重症肺部感染患者通气情况的应用价值。方法:选取88例重症肺部感染患者,采用半定量方法对肺部超声征象进行评分,以CT检查结果为金标准,分析肺部超声评分与患者肺通气的关系;同时分析存活和死亡患者临床资料、肺部超声评分的差异,以及肺部超声评分预测患者死亡的价值。结果:88例患者全肺超声评分平均为（18.50±2.12）分,全肺CT值平均为（-620.50±88.13） HU,不通气/低通气肺组织比例平均为（10.41±3.35）%,正常通气肺组织比例平均为（71.54±6.69）%,过度通气肺组织比例平均为（17.65±4.11）%;患者肺部超声评分与全肺CT值、不通气/低通气肺组织比例呈正相关（r=0.775、0.648, P<0.05）,与正常通气肺组织比例、过度通气肺组织比例无明显相关性（r=-0.170、0.046, P>0.05）;死亡组患者年龄、糖尿病比例、APACHEⅡ评分、肺泡-动脉氧分压差、机械通气治疗和肺部超声评分分别为（59.28±8.12）岁、44.83%、（22.19±2.40）分、（344.40±82.29） mmHg、72.41%和（20.20±1.72）分,明显高于存活组（P<0.05）,而氧合指数为（104.42±21.18）,明显低于存活组（P<0.05）;Logistic回归分析结果显示:年龄、APACHEⅡ、肺部超声评分是重症肺部感染患者死亡的影响因素（OR=1.758、2.841、2.440, P<0.05）;肺部超声评分预测重症肺部感染患者死亡的ROC曲线下面积为0.901（95%CI:0.836~0.966）,截断值为20分,灵敏性和特异性分别为82.80%和84.70%。结论:肺部超声可以作为重症肺部感染患者肺通气的评估指标,同时其在预测患者预后方面有一定应用价值。     

Reversal of pulmonary vascular remodeling in pulmonary hypertensive rats

Pulmonary hypertension is responsible for significant mortality and morbidity among newborns and infants. The pathology is characterized by pulmonary vascular remodeling with medial hypertrophy and adventitial thickening, leading to decreased gas exchange. Since it is unknown if these abnormalities are reversible, we analyzed these vascular changes in pulmonary hypertensive rats. Exposure of rats to hypobaric hypoxia for 4 weeks induced clinical signs of pulmonary hypertension, such as increased right ventricular systolic pressure, increased right ventricular weight and considerable pulmonary vascular remodeling. The vascular changes were associated with the expression of Non -Muscle Myosin Heavy Chain B in the pre-acinar vessels and an increased expression of alpha Smooth Muscle Actin, Smooth Muscle Myosin Heavy Chain 2 and Calponin in the intra-acinar vessels. The right ventricular systolic pressure and right ventricular weight gradually decreased after specific periods of recovery in normoxia, although this reversal did not reach baseline levels after six weeks at normoxia. However, the cellular changes in the pulmonary vasculature were completely reversed. Development of pulmonary hypertension is associated with an increase of synthetic perivascular cells in the pre-acinar arteries and an aberrant differentiation of perivascular cells in the smallest intra-acinar arteries. These cellular and structural changes in the pulmonary vasculature are completely reversible after recovery in normoxia.     

A case of pulmonary capillary hemangiomatosis with pulmonary fibrosis associated with MMP-9 related pulmonary remodeling

Pulmonary capillary hemangiomatosis (PCH) is a rare cause of pulmonary hypertension. It is characterized capillary proliferation within the alveolar septa. Here, we report a case of PCH with extensive pulmonary fibrosis. A 52-year-old man with a clinical diagnosis of non-specific interstitial pneumonia died of respiratory failure with severe pulmonary hypertension. Autopsy revealed pronounced right ventricle hypertrophy and pulmonary fibrosis. Consistent with clinical diagnosis, histological examination revealed diffuse pulmonary fibrosis, in addition, it also disclosed marked capillary proliferation within the alveolar septa as well as the fibrotic pulmonary stroma, suggesting the presence of PCH. Hemosiderin-laden macrophages had accumulated in the capillary proliferative area, and bronchiolar-type metaplasia was conspicuous in the fibrotic lesion. Proliferated capillaries were surrounded by fine collagen and α-smooth muscle actin-positive myofibroblasts. Immunohistochemistry revealed that type IV collagen around capillaries in the area of the PCH without inflammation disappeared in the area with inflammation. In addition, the PCH lesion contained significant numbers of macrophages expressing matrix metalloproteinase (MMP) 9 and type II pneumocytes positive for vascular endothelial growth factor. Although pulmonary fibrosis is a distinctive disease entity, different from PCH, MMP-9-driven destruction of the basement membrane may promote unusual pulmonary remodeling, which, in this case, resulted in extensive pulmonary fibrosis.     

Pure pulmonary arterial tumour embolism--a rare cause of pulmonary infarction

Pulmonary vascular involvement in the natural course of spread of malignant tumours can produce respiratory distress and often manifests as lymphangitis carcinomatosis or carcinomatous arteriopathy. Pulmonary infarction due to arterial tumour embolism is infrequent. This is a report of a treated case of cervical cancer in middle-aged woman who presented after three years with infarction of the lungs following arterial tumour emboli.     

Pathogenesis of pulmonary edema: learning from high-altitude pulmonary edema

Pulmonary edema is a problem of major clinical importance resulting from a persistent imbalance between forces that drive water into the airspace of the lung and the biological mechanisms for its removal. Here, we will review the fundamental mechanisms implicated in the regulation of alveolar fluid homeostasis. We will then describe the perturbations of pulmonary fluid homeostasis implicated in the pathogenesis of pulmonary edema in conditions associated with increased pulmonary capillary pressure, namely cardiogenic pulmonary edema and high-altitude pulmonary edema (HAPE), with particular emphasis on the latter that has provided important new insight into underlying mechanisms of pulmonary edema. We will provide evidence that impaired pulmonary endothelial and epithelial nitric oxide synthesis and/or bioavailability may represent a central underlying defect predisposing to exaggerated hypoxic pulmonary vasoconstriction, and, in turn, capillary stress failure and alveolar fluid flooding. We will then demonstrate that exaggerated pulmonary hypertension, while possibly a prerequisite, may not always be sufficient to cause HAPE, and how defective alveolar fluid clearance may represent a second important pathogenic mechanism. Finally, we will outline, how this new insight gained from studies in HAPE, may be translated into the management of pulmonary edema and hypoxemia related disease states in general.