载脂蛋白E基因敲除小鼠动脉粥样硬化早期血管外膜血管细胞黏附分子1和细胞间黏附分子1的表达

目的探讨血管外膜血管细胞黏附分子1和细胞间黏附分子1在动脉粥样硬化病灶形成及发展中的作用。方法 6周龄载脂蛋白E基因敲除小鼠和野生型C57BL/6小鼠,高脂饮食喂养2、4和8周,选取升主动脉制备连续切片,部分切片行Movat染色,观察组织形态学变化并测量外膜厚度的变化;部分切片用免疫组织化学法观察不同阶段血管外膜及内膜血管细胞黏附分子1和细胞间黏附分子1表达的动态变化。结果 6周龄载脂蛋白E基因敲除小鼠和各个时间点的C57BL/6小鼠均未观察到内膜损伤的任何迹象,主动脉外膜厚度亦无显著变化,外膜均无血管细胞黏附分子1的表达;高脂喂养2周后,载脂蛋白E基因敲除小鼠血管外膜厚度增加,但在内膜仍无肉眼可见病灶,此时外膜血管细胞黏附分子1呈现弱阳性表达;高脂喂养4周和8周后,载脂蛋白E基因敲除小鼠血管外膜厚度逐渐增加,内膜出现泡沫细胞,纤维斑块,外膜及内膜损伤处血管细胞黏附分子1表达增强。载脂蛋白E基因敲除小鼠随着高脂喂养时间延长,主动脉外膜及内膜细胞间黏附分子1的表达也增加,但C57BL/6小鼠血管外膜细胞间黏附分子1表达量少且稳定,各时间点之间无明显差异。结论载脂蛋白E基因敲除小鼠随着高脂喂养时间延长血管外膜血管细胞黏附分子1和细胞间黏附分子1的表达增加。     

急性冠状动脉综合征患者冠状动脉循环粘附分子的变化

目的探讨急性冠状动脉综合征患者冠状动脉循环血浆细胞间粘附分子1和血管细胞粘附分子1水平变化的临床意义.方法应用酶联免疫吸附法检测65例冠心病患者(30例急性冠状动脉综合征,35例稳定型心绞痛)及27例对照者冠状动脉循环(冠状静脉窦-主动脉根部)血浆细胞间粘附分子1和血管细胞粘附分子1水平,比较其水平变化与不同冠心病类型之间的关系.结果急性冠状动脉综合征组冠状静脉窦和主动脉根部血浆细胞间粘附分子l和血管细胞粘附分子1水平明显高于稳定型心绞痛组和对照组(P＜0.05);急性冠状动脉综合征组冠状动脉循环(冠状静脉窦与主动脉根部的差值)血浆细胞间粘附分子1和血管细胞粘附分子1水平明显高于稳定型心绞痛组和对照组(P＜0.01).稳定型心绞痛组和对照组冠状静脉窦、主动脉根部和冠状动脉循环血浆细胞间粘附分子1和血管细胞粘附分子1水平无明显差别(P＞0.05).血浆细胞间粘附分子1和血管细胞粘附分子1水平与冠状动脉病变受累支数无关.结论急性冠状动脉综合征时血浆细胞间粘附分子1和血管细胞粘附分子1浓度显著升高,冠状动脉循环血浆细胞间粘附分子1和血管细胞粘附分子1变化反映冠状动脉炎症活动程度,细胞粘附分子参与斑块的不稳定.     

脂多糖诱导的血管外膜炎症对兔股动脉内膜增生的影响及机制

通过用脂多糖诱导兔股动脉外膜炎症,来观察其对内膜增生的影响,并用免疫组织化学法观察股动脉壁核因子κB p65的表达情况,从而探讨外膜炎症对内膜增生影响的分子机制。高脂饮食饲养新西兰大耳白兔24只,两侧股动脉按实验要求分为分为脂多糖组(n=24)和对照组(n=24)。制备用脂多糖诱导的外膜炎症模型,于术后0天(n=8)、3天(n=8)和2周(n=8)处死动物取得股动脉标本,HE染色观察形态学变化和内膜增生情况,同时用免疫组织化学方法镜下观察核因子κB p65在动脉壁的表达。结果发现3天和2周时,脂多糖组血管外膜和内膜面炎症细胞明显增多。在3天时,脂多糖组血管内皮细胞和外膜细胞在胞浆中出现核因子κB p65阳性表达。计算机图象分析发现,2周时脂多糖组内膜面积(0.93±0.14mm2)和对照组(0.75±0.15mm2)相比有明显差异(P<0.05)。结果提示脂多糖诱导的血管外膜炎症可导致兔股动脉内膜增生,而在内膜增生之前伴随着血管内皮细胞和外膜细胞核因子κBp65的阳性表达,外膜炎症可能是通过激活上述细胞中的核因子κB从而启动炎性细胞因子的转录导致内膜增生。     

动脉损伤后血管外膜炎症细胞浸润及曲尼司特的干预效应

目的研究动脉内膜损伤后血管外膜炎症细胞的浸润,以及曲尼司特对上述指标的干预。方法球囊拉伤兔髂动脉内膜,随机分为对照组与曲尼司特组,在术后1 h、1 d3、d、7 d、14 d取髂动脉,通过组织学检查,免疫组化方法检测血管外膜炎症细胞的浸润及曲尼司特对它们的影响。结果(1)术后外膜可见T淋巴细胞出现,逐渐增高,于7 d达到最高峰,曲尼司特组较对照组无变化。(2)术后外膜见中性粒细胞、巨噬细胞、肥大细胞表达,均在3 d达到最高峰,曲尼司特组各时间点明显下降。结论(1)内膜损伤后,外膜炎症细胞浸润,以巨噬细胞、中性粒细胞为主(。2)曲尼司特降低血管各层增生,增加管腔面积,减少巨噬细胞、中性粒细胞、肥大细胞在血管外膜的浸润表达,对T淋巴细胞无影响。     

普伐他汀和辛伐他汀对载脂蛋白E缺陷小鼠主动脉粥样硬化形成及主动脉壁血管细胞粘附分子-1表达的影响

为观察普伐他汀和辛伐他汀对载脂蛋白E缺陷小鼠主动脉粥样斑块形成的影响及主动脉壁血管细胞粘附分子 1表达的影响 ,将载脂蛋白E缺陷小鼠分为普伐他汀组 (每天 10mg/kg)、辛伐他汀组 (每天 5mg/kg)和阳性对照组 (等量生理盐水 ) ,从主动脉血管根部连续切片 ,常规HE染色 ,计算机图像扫描 ,分析主动脉粥样硬化斑块的面积和斑块占管腔面积等 ;采用免疫组织化学及Western杂交方法测定主动脉壁血管细胞粘附分子 1表达。结果发现 ,除降胆固醇作用外 ,普伐他汀和辛伐他汀皆延缓斑块形成 ,与对照载脂蛋白E缺陷小鼠比 ,用药组小鼠的主动脉粥样斑块明显缩小 ;普伐他汀和辛伐他汀还明显抑制载脂蛋白E缺陷小鼠主动脉壁血管细胞粘附分子 1的表达 ;其中 2药对 14和 2 4周龄小鼠主动脉壁血管细胞粘附分子 1表达的抑制作用强于 34周龄小鼠。结果提示 ,普伐他汀和辛伐他汀可延缓或缩小载脂蛋白E缺陷小鼠主动脉粥样斑块的形成 ,抑制或下调主动脉壁血管细胞粘附分子 1表达 ,其效果与降胆固醇作用不成比例 ,可能是独立于调脂作用以外的抗动脉粥样硬化机制     

外膜是血管病变的积极参与者

长期以来对动脉外膜与血管病灶形成关系的研究较少。一般认为动脉外膜炎性细胞聚集是晚期动脉粥样硬化病灶的病理学特征之一,外膜炎症的严重程度与病灶的严重程度呈正相关。近年来有报告发现动脉外膜炎症是诱发动脉内膜粥样硬化病灶形成的早期事件。研究发现血管成形术后动脉还原型辅酶Ⅱ氧化酶活性增强,氧自由基生成增多,刺激外膜成纤维细胞增殖、肌化并向内膜迁移,参与新内膜增生,促使血管再狭窄。由此抑制外膜成纤维细胞还原型辅酶Ⅱ氧化酶活性成为有关基因治疗的新途径。     

细胞间粘附分子1、血管细胞粘附分子1和肿瘤坏死因子α在人动脉粥样硬化病灶中的表达及意义

为研究细胞间粘附分子 1、血管细胞粘附分子 1和肿瘤坏死因子α在人正常冠状动脉与冠状动脉粥样硬化组织中的表达及病理学意义 ,采用免疫组织化学SP法 ,分别检测细胞间粘附分子 1、血管细胞粘附分子 1和肿瘤坏死因子α在人正常冠状动脉与冠状动脉粥样硬化组织中的表达情况。结果发现 ,细胞间粘附分子 1、血管细胞粘附分子 1和肿瘤坏死因子α在动脉粥样硬化组织中的内皮细胞、平滑肌细胞、巨噬细胞均有表达。三者在脂纹期的表达分别为 5 0 .0± 10 .9、5 1.8± 6 .0和 13.9± 2 .8,在纤维斑块期分别为 2 3.1± 7.3、37.2± 9.7和 2 3.0± 6 .0 ,在粥样斑块期分别为 17.5± 4 .9、18.6± 5 .5和 38.0± 10 .0 ,明显高于对照组 (2 .2± 1.4、2 .2± 1.2和 7.8± 2 .2 ,分别为P<0 .0 1)。细胞间粘附分子 1和血管细胞粘附分子 1与肿瘤坏死因子α呈正相关 (前者r=0 .344、P <0 .0 1,后者r=0 .5 2、P <0 .0 1)。实验结果提示 ,细胞间粘附分子 1和血管细胞粘附分子 1在内皮细胞、平滑肌细胞和巨噬细胞高表达可能参与动脉粥样硬化发生发展过程中的某些环节。肿瘤坏死因子α的表达与细胞间粘附分子 1和血管细胞粘附分子 1的表达及动脉粥样硬化病变程度具有相关性。     

移植心脏冠状动脉血管病尸检病理分析

目的:提高对移植心脏脏冠状动脉血管病病变的认识。方法:对尸检病例心脏进行HE染色并用免疫组织化学染色及EBER原位杂交检测等方法,对浸润淋巴细胞进行病理分析并文献复习。结果:①移植心脏冠状动脉血管病主要病变表现为不同程度,不同部位的冠状动脉内膜弥散性、同心圆样内膜增生、散在淋巴、单核细胞浸润、部分伴脂质沉积、血栓形成及较少钙化;②心肌细胞可表现为局灶变性、坏死及纤维瘢痕形成,部分出现明显心肌纤维化;③血栓可出现于冠状动脉主干及各分枝、附着于心室壁及肺动脉内;④移植心脏冠状动脉血管病可伴有急性细胞排斥反应,浸润淋巴细胞可单纯出现在心肌间质内,也可以表现为增厚冠状动脉血管内膜同时伴发淋巴细胞浸润,多次发生急性细胞排斥反应,可以加重移植心脏冠状动脉血管病的发病。结论:移植心脏冠状动脉血管病变临床不易早期发现,确诊需要冠状动脉血管造影、血管内超声等影像学检查;移植心脏冠状动脉血管病常伴发急性细胞排斥反应。     

低密度脂蛋白不同亚组分对血管内皮细胞粘附分子表达的不同影响

通过观察低密度脂蛋白不同亚组分对细胞间粘附分子 1和血管细胞粘附分子 1表达的影响 ,来探讨低密度脂蛋白致动脉粥样硬化的分子机制。采用两次超速离心法分离制备大颗粒疏松低密度脂蛋白和小颗粒致密低密度脂蛋白 ,在内皮细胞培养基中分别加入不同剂量的天然或氧化型小颗粒致密或大颗粒疏松这 4种脂蛋白 ,37℃温育 12h ,用细胞酶联免疫吸附法检测细胞间粘附分子 1和血管细胞粘附分子 1蛋白的表达。结果发现 ,不同剂量的 4种脂蛋白均可使细胞间粘附分子 1和血管细胞粘附分子 1蛋白表达增高 ,天然或氧化型小颗粒致密低密度脂蛋白增加内皮细胞表面细胞间粘附分子 1和血管细胞粘附分子 1蛋白表达呈剂量依赖性。比较相同浓度的 4种脂蛋白的作用时发现 ,2 5mg和 5 0mg小颗粒致密低密度脂蛋白增加细胞间粘附分子 1和血管细胞粘附分子 1表达的作用强于大颗粒疏松低密度脂蛋白 ,但差异无统计学意义 ;10 0mg天然小颗粒致密低密度脂蛋白增加细胞间粘附分子 1和血管细胞粘附分子 1表达的作用强于其它三种脂蛋白 (细胞间粘附分子 1的表达分别为 0 .83± 0 .0 9、0 .6 6± 0 .15、0 .80± 0 .0 7和 0 .76± 0 .0 8;血管细胞粘附分子 1的表达分别为 0 .37± 0 .0 4、0 .2 8± 0 .0 4、0 .2 9± 0 .0 2和0 .2 7± 0 .0     

血管外膜炎症和动脉粥样硬化

动脉粥样硬化是一种炎症性疾病的假说已逐渐为人们所接受,然而在对其研究过程中,人们长期把注意力集中于血管内膜.最近证据表明,血管外膜炎症和血管外膜细胞也参与动脉粥样硬化的形成过程.本文拟对血管外膜炎症和动脉粥样硬化的关系作一综述.     

茶多酚对兔颈总动脉血管成形术后再狭窄的影响

为探讨茶多酚对血管成形术后动脉中膜平滑肌增生及胶原增生的影响,以及与组织型纤溶酶原激活物和血管紧张素Ⅱ活性改变的关系,将雄性新西兰白兔30只随机分为对照组、低剂量茶多酚组和高剂量茶多酚组,用球囊导管剥脱右颈总动脉内皮,造成内皮及中膜损伤,分别在术前、术后3、7、11、14、22和28 d采动脉血应用酶联免疫法测血浆组织型纤溶酶原激活物活性及放射免疫法测血管紧张素Ⅱ血清水平,术后28 d处死动物并取右颈总动脉观察动脉中膜平滑肌和胶原增生程度.结果发现,高剂量茶多酚组组织型纤溶酶原激活物血浆活性为0.169±0.067 IU/L,低剂量茶多酚组为0.141±0.043 IU/L,对照组为0.126±0.043 IU/L,高剂量茶多酚组高于对照组和低剂量茶多酚组,差异具有显著性(P<0.05).高剂量茶多酚组血管紧张素Ⅱ血清水平为1 229±283 ng/L,低剂量茶多酚组为1 302±284 ng/L,对照组为1 309±263 ng/L,三组动物术后血管紧张素Ⅱ血清水平比较差异无显著性.高剂量茶多酚组动脉中膜胶原含量为50.1%+5.82%、低剂量茶多酚组为56.7%±2.3%,对照组为62.8%±2.1%,高剂量茶多酚组低于对照组及低剂量茶多酚组,差异具有显著性 (P<0.05);低剂量茶多酚组低于对照组,差异具有显著性(P<0.001).高剂量茶多酚组中膜平滑肌细胞计数为0.022±0.006/μm2,低剂量茶多酚组为0.034±0.008/μm2,对照组为0.033±0.007/μm2,高剂量茶多酚组低于对照组及低剂量茶多酚组,差异具有显著性(P<0.01).结果提示,高剂量茶多酚可提高血管成形术后血浆组织型纤溶酶原激活物活性,对血管紧张素Ⅱ血清水平无显著性影响,可抑制动脉中膜胶原及平滑肌细胞的增生,这可能有助于减轻或预防动脉血管成形术后再狭窄.     

Localisation of mRNA for JE/MCP-1 and its receptor CCR2 in atherosclerotic lesions of the ApoE knockout mouse

MCP-1 has potent chemotactic activity for monocytes and is strongly implicated in the pathogenesis of atherosclerosis. In the present study, we have used in situ hybridisation to examine the gene expression of JE, the murine homologue of MCP-1, and its receptor, CCR2, during the development of atherosclerotic lesions in the ApoE knockout mouse. Interestingly, the earliest expression of JE detected during lesion development was found to be localised in mesenchymal cells in the adventitia and not in the intima. Macrophages were subsequently found to accumulate in these affected regions of the adventitia and these cells were found to express high levels of JE. At this stage, early macrophage-rich lesions with high expression of JE were also seen in the intima, but expression of mRNA for the receptor for JE (CCR2) was only found on adventitial macrophages and not in the intima. This sequence of events suggests that adventitial inflammation may be an important early event in lesion development and responsible for the subsequent accumulation of macrophages in the intima possibly by recruitment from the adventitia as well as via the vessel lumen.     

Interleukin-1 plays a major role in vascular inflammation and atherosclerosis in male apolipoprotein E-knockout mice

OBJECTIVE: To examine the role of the balance between interleukin (IL)-1 and IL-1 receptor antagonist (IL-1Ra) in atherosclerosis and vascular inflammation. METHODS: Transgenic (Tg) mice overexpressing either secreted IL-1Ra or intracellular IL-1Ra1 as well as IL-1Ra-deficient mice (IL-1Ra -/-) were crossed with apolipoprotein E-deficient mice (ApoE -/-). RESULTS: In males fed a cholesterol-rich diet for 10 weeks, average atherosclerotic lesion area within aortic roots was significantly decreased in ApoE -/- secreted IL-1Ra Tg (-47%) and ApoE -/- intracellular IL-1Ra1 Tg (-40%) mice as compared to ApoE -/- non-Tg controls. The extent of sudanophilic lesions was reduced within the thoraco-abdominal aorta in ApoE -/- secreted IL-1Ra (-53%) and ApoE -/- intracellular IL-1Ra1 (-67%) Tg mice. In parallel experiments, we observed early mortality and illness among double deficient mice, whereas ApoE -/- IL-1Ra +/+ and ApoE +/+ IL-1Ra -/- mice were apparently healthy. After 7 weeks of diet, ApoE -/- IL-1Ra -/- mice exhibited massive aortic inflammation with destruction of the vascular architecture, but no signs of atherosclerosis. ApoE -/- IL-1Ra +/+ had atherosclerosis and a moderate inflammatory reaction, whereas ApoE +/+ IL-1Ra -/- mice were free of vascular lesions. Macrophages were present in large amounts within inflammatory lesions in the adventitia of ApoE -/- IL-1Ra -/- mice. CONCLUSION: Our results demonstrate that the IL-1/IL-1Ra ratio plays a critical role in the pathogenic mechanisms leading to vascular inflammation and atherosclerosis in ApoE -/- mice.     

Lymphangiogenesis promotes inflammation and neointimal hyperplasia after adventitia removal in the rat carotid artery

Lymphatic vessels exist in adventitia in the atherosclerotic coronary artery and play an important role in the inflammatory and immune response. After adventitia removal, the carotid wall of rat model showed significantly increased ratio of intimal to medial area (I/M ratio), the number of adventitial lymphatic vessels (Ad-LV) and microvessels (Ad-MV), and macrophage index and expression of VEGF-C, VEGFR-3, PDGF-B and PDGFR-beta. The I/M ratio was significantly correlated with Ad-LV and macrophage index but not Ad-MV. These results suggest that adventitial lymphangiogenesis is stimulated by growth factors released by inflammatory cells in vasculature after adventitia removal, and these neogenetic lymph vessels in turn promote intimal inflammation and hyperplasia, probably via delivery and activation of inflammatory cells.     

EMAP-II downregulation contributes to the beneficial effects of rapamycin after vascular injury

AIMS: Neointima formation after vascular injury is strongly associated with inflammation. Rapamycin inhibits human neointima formation and reduces expression of the proinflammatory cytokine endothelial-monocyte activating peptide II (EMAP-II) in vitro. Here we investigated the interplay between EMAP-II and rapamycin after vascular injury in vivo. METHODS AND RESULTS: In a mouse model of vascular injury, mice were either not treated, given everolimus, a rapamycin derivate, or subjected to simultaneous challenge with everolimus and EMAP-II. EMAP-II expression was measured in coronary artery smooth muscle cells (CASMC) and monocytic cells in vitro and in patients after percutaneous coronary intervention (PCI). After vascular injury, rapamycin reduced neointima formation and adventitial thickening. Immunohistochemistry revealed reduced EMAP-II protein expression and suppressed recruitment of inflammatory cells. Simultaneous challenge with EMAP-II counteracted these effects of rapamycin. Expression of EMAP-II and its inhibition by rapamycin was confirmed in CASMC and monocytic cells. In patients, EMAP-II upregulation was confined to PCI of distal coronary artery segments and profoundly suppressed by oral rapamycin treatment. CONCLUSION: These data suggest important yet unrecognized roles of EMAP-II and adventitial inflammation in neointima formation: Through inhibition of EMAP-II, rapamycin reduces the recruitment of inflammatory cells to the adventitia and supports an early and bland healing.     

The role of the adventitia in vascular inflammation

Traditional concepts of vascular inflammation are considered "inside-out" responses centered on the monocyte adhesion and lipid oxidation hypotheses. These mechanisms likely operate in concert, holding the central tenet that the inflammatory response is initiated at the luminal surface. However, growing evidence supports a new paradigm of an "outside-in" hypothesis, in which vascular inflammation is initiated in the adventitia and progresses inward toward the intima. Hallmarks of the outside-in hypothesis include population of the adventitia with exogenous cell types, including monocytes, macrophages, and lymphocytes, the phenotypic switch of adventitial fibroblasts into migratory myofibroblasts, and increased vasa vasorum neovascularization. The resident and migrating cells deposit collagen and matrix components, respond to and upregulate inflammatory chemokines and/or antigens, and regulate the local redox state of the adventitia. B cells and T cells generate local humoral immune responses against local antigen presentation by foam cells and antigen presenting cells. These events result in increased local expression of cytokines and growth factors, evoking an inflammatory response that propagates inward toward the intima. Ultimately, it appears that the basic mechanisms of cellular activation and migration in vascular inflammation are highly conserved across a variety of cardiovascular disease states and that major inflammatory events begin in the adventitia.     

Significance of adventitial inflammation of the coronary artery in patients with unstable angina: results at autopsy

A quantitative analysis of adventitial inflammation of the coronary artery with intimal lesions is described in 12 patients who suffered coronary death and had had unstable angina (crescendo angina) at rest (group 1). After autopsy in these patients we examined epon-embedded cross sections by light and electron microscopy, paying particular attention to the adventitia, and compared these results with those in six patients who had had angina but died of noncardiac causes (group 2) and those in 22 patients who did not have angina (group 3). Of the 132 segments from group 1 patients, 39 (30%) were narrowed 76% to 100% by atherosclerotic plaque (group 2, 27%; group 3, 1%), and 23 (17%) had occlusive thrombi. Of the 264 sections (two from each segment) from group 1 that were examined, 98 (37%) (group 2, 15%; group 3, 9%) revealed clustered infiltration of inflammatory cells in the adventitia, half of which were associated with vascular nerve involvement. These findings in the adventitia may be related to the vasospastic component of unstable angina.     

Coronary artery lesions in Takayasu arteritis: Pathological considerations

This communication reviews the clinical and pathological features of coronary artery lesions in Takayasu arteritis. The incidence of coronary artery involvement has been reported to be 9% to 10%, and is observed mainly in autopsy cases because coronary artery disease is usually not evident until the occurrence of angina pectoris or myocardial infarction, or after the onset of congestive heart failure. On the basis of pathological features, the following three types of coronary artery lesions can be distinguished: type 1, stenosis or occlusion of the coronary ostia and the proximal segments of the coronary arteries; type 2, diffuse or focal coronary arteritis, which may extend diffusely to all epicardial branches or may involve focal segments, so-called skip lesions; and type 3, coronary aneurysm. Most of the coronary artery lesions in Takayasu arteritis are of type 1. Narrowing of the coronary arteries is mainly due to the extension of the inflammatory processes of proliferation of the intima and contraction of the fibrotic media and adventitia from the ascending aorta. In some cases, coronary stenosis may be caused by coronary arteritis as skip lesions in Takayasu arteritis, but even in these cases the lesions have been reported to affect mainly the proximal segments of the coronary arteries. Diffuse lesions of the coronary artery and coronary artery aneurysm seem to be very rare in Takayasu arteritis. Other causes of coronary ostial stenosis, coronary arteritis and coronary artery aneurysm are also discussed.