氟伐他汀抑制球囊损伤后兔的血管内膜增殖

目的：探讨兔髂动脉急性损伤后，氟伐他汀对血管内膜增殖的抑制作用及机制。 方法： 给新西兰大耳白兔行右髂动脉球囊导管内膜剥脱术，术后灌胃予氟伐他汀（8 mg·kg-1·d-1）治疗28 d，术前、术后3 h及3 d用放射免疫法测定血清中内皮素-1、血栓素A2和前列环素浓度；28 d后HE染色观察血管内膜增生情况，免疫组织化学方法检测细胞外基质的变化。结果： ① 兔髂动脉急性损伤后血清内皮素-1及血栓素A2浓度即明显增加，前列环素水平则显著下降；氟伐他汀治疗显著抑制内皮素-1和血栓素A2的升高；提高血清前列环素的水平；② 氟伐他汀治疗减轻了内膜TGF-β1的过度表达及细胞外基质（FN、LN）的沉积；③ 氟伐他汀显著抑制了内膜的增殖和肥厚。结论：氟伐他汀治疗抑制血管损伤后血栓的形成，减轻了内膜的增殖及内膜中细胞外基质的沉积。     

损伤血管内膜增生的研究

血管损伤后内膜增生（IH）是血管外科重建、血管腔内治疗术后发生狭窄或闭塞的主要原因，也是血管外科长期以来拯待解决的难题。有关的研究一直是血管外科临床和基础研究的重点。     

选择性清除单核／巨噬细胞对血管损伤后内膜增生影响的研究

目的应用脂质体输送系统选择性清除单核／巨噬细胞，探讨血管损伤后抑制内膜增生的有效途径。方法采用反相蒸发技术将clodronate用脂质体包裹，在36只大鼠颈动脉损伤模型前1d、损伤后6d，分别尾静脉注射15mg／kg体重的脂质体包裹clodronate（112组。12只）、clodronate溶液（FC组，8只）、等量生理盐水（saline组，9只）或等量空脂质体（EL组，7只），14天后颈总动脉切片行HE、VG染色，用图象分析软件测定颈动脉管腔面积、增生内膜面积、中膜面积，并计算增生内膜与中膜面积比值（N／M）、管腔狭窄率（％）。另取10只大鼠尾静脉注射荧光标记的脂质体包裹clodronate（5只）或等量荧光标记的空脂质体（5只），颈总动脉损伤后1天下腔静脉抽血分离白细胞，并取颈总动脉、肝脏、脾脏，冰冻切片后在激光扫描共聚焦显微镜下观察荧光物质分布。结果包裹、未包裹clodronate的脂质体、罗丹明标记脂质体的平均直径分别为（213±20）nm、（（198±14）nm、（209±19）nm，包裹率17．6％-19．0％，脂质体中clodronate浓度（7．6±1．1）mg／ml；各组大鼠损伤动脉内膜均有明显增生，但LC组血管内膜增生明显较其它3组明显减轻，表现为N／M、管腔狭窄率（％）明显低于其它3组相应值（P〈0．01）；FC组或EL组对血管内膜增生无明显影响（与saline组比，P〉0．05）。各组间颈总动脉中膜面积无明显差别。尾静脉注射荧光标记脂质体48h后，大鼠左颈总动脉、静脉血中白细胞、脾脏、肝脏中可以发现单核／巨噬细胞中有荧光标记物积聚，其中LC组大鼠上述组织中荧光标记物较EL组者明显减少，表明脂质体包裹clodronate可明显减少体内单核／巨噬细胞数量。结论通过clodronate的脂质体输送系统将巨噬细胞暂时灭活、清除，可以预防血管损伤后的血管再狭窄。     

跨膜蛋白66过表达减轻大鼠颈动脉球囊损伤后内膜增生

目的研究跨膜蛋白66(TMEM66)在大鼠颈动脉球囊损伤后内膜增生中的作用。方法将SD大鼠随机分为对照组,左侧颈动脉球囊损伤组和TMEM66过表达组(n=10)。HE染色检测各组血管内膜增生情况。Western blot、q-PCR及IHC分别检测颈动脉血管中TMEM66的表达。CCK8和划痕实验分别检测TMEM66过表达后原代培养血管平滑肌细胞(VSMC)的增殖和迁移。结果颈动脉球囊损伤血管中TMEM66的表达量较对照组显著下降(P0.05)。球囊损伤后血管内膜明显增生,慢病毒特异性转染TMEM66过表达可显著逆转血管内膜增生(P0.05)。上调TMEM66能够改善PDGF所诱导的VSMC增殖和迁移(P0.05)。结论 TMEM66可以改善大鼠颈动脉球囊损伤后内膜增生。     

动脉粥样硬化大鼠血管损伤后局部组织学结构的变化

目的建立大鼠颈总动脉球囊损伤模型，了解血管成形术后再狭窄的发生规律及病理机制。方法在大鼠动脉粥样硬化病变的基础上，使用2F球囊导管损伤大鼠左侧颈总动脉，观察术后不同时期内膜、中膜增生的动态改变；对血管壁增殖的细胞进行鉴定；观察血管壁平滑肌细胞表型标志物SMα—actin表达的变化。结果损伤后7天薪生内膜开始形成，至3月时内膜增厚达最大，管腔明显狭窄，损伤动脉壁可见细胞大量增殖，大部分为平滑肌细胞。损伤早期血管壁表达SMα—actin减少，至损伤后期逐渐恢复至原有水平。结论应用球囊导管可以成功建立大鼠血管损伤动物模型，损伤后新生内膜增生导致管腔狭窄，平滑肌细胞的表型改变、迁移及增殖是内膜过度增生的病理基础。     

球囊损伤后血管重塑中内皮依赖性因子的作用及其相互关系

探讨球囊损伤后血管重塑中血红素氧化酶-1(HO-1)/一氧化碳(CO)与一氧化氮合酶(NOS)/一氧化氮(NO)两系统的作用及其相互关系.实验兔随机分为7组:对照组、假手术组、精氨酸组、亚硝基组、胆固醇组、血红素组和叶啉锌组.对照组喂普通饲料,其余6组喂饲含1.5%胆固醇饲料,精氨酸组和亚硝基组饮水同时给予L-精氨酸或亚硝基-L-精氨酸甲酯,血红素组和叶啉锌组同时分别予氯化血红素或锌原叶啉-9腹腔内注射,2周后各实验组行右侧颈总动脉球囊损伤术,术后续原饲养和给药8周.研究发现:与胆固醇组比较,精氨酸组cNOS活性、NO生成量显著增加,内皮素-1、NF-kB活性显著降低,内膜厚度和狭窄率显著减小[(292.65±22.48)μm,39.8%±2.51%](均P<0.01);亚硝基组上述指标变化与精氨酸组相反(均P<0.01),内膜厚度和狭窄率变化不显著[(466.49±61.34)μm,56.1%±6.81%](P>0.05);血红素组HO活性、CO生成量显著增加,内皮素-1、NF-kB活性显著降低,内膜厚度和狭窄率最小[(281.47±21.10)N,m,38.8%±2.43%](均P<0.01);叶啉锌组各指标变化与血红素组相反,内膜厚度和狭窄率最大[(698.71±58.37)μm,78.5%±6.10%](均P<0.01).结果表明NOS/NO与HO-1/CO系统在球囊损伤后血管重塑中发挥互补及代偿作用,HO-1/CO系统可能通过代偿和调节NOS/NO系统以及下调内皮素-1、NF-kB活性从而抑制血管损伤后不良重塑.     

细胞色素2J3基因转染减轻大鼠胸主动脉球囊损伤后血管狭窄程度的初步机制

血管介入治疗是目前治疗外周血管阻塞性疾病和心脑血管疾病常用的方法,但术后血管再狭窄（Restenosis,RS）是血管介入治疗常见的主要问题。目前已知RS至少包括下述病理变化：（1）血管内皮细胞损伤、功能障碍;（2）血管平滑肌细胞对缩血管物质和促细胞分裂物质反应性增强而异常增殖,致增殖与凋亡调控失衡;（3）损伤局部促凝物质增加,血小板及白细胞易与血管壁发生黏附,附壁血栓形成。     

纤维蛋白沉积与大鼠主动脉球囊损伤后肌内膜增殖的关系

目的：利用大鼠胸主动脉球囊内皮剥脱术模型，探讨纤维蛋白（原）与肌内膜增殖的关系。方法：将６４只Ｗｉｓｔａｒ大鼠随机分为正常组、假手术组和剥脱组。剥脱组大鼠又分别在术后１０ｍｉｎ、１、３、７、１４、２１天处死取材。结果：大鼠胸主动脉免疫组织化学研究发现，正常组和假手术组大鼠血管壁无纤维蛋白（原）沉积，术后１０ｍｉｎ在血管腔表面即有一层致密的纤维蛋白（原）沉积，然后随着术后时间的延长，纤维蛋白（原）逐渐渗入到增殖的新生内膜中，中膜中未见有纤维蛋白（原）的沉积。结论：纤维蛋白（原）可能在内皮剥脱后的血管平滑肌细胞增殖中起一定作用。     

尾加压素Ⅱ对大鼠胸主动脉球囊损伤后血管重塑的作用

目的： 探讨尾加压素Ⅱ(UII)在血管损伤后重塑过程中的作用。方法: 建立大鼠胸主动脉球囊拉伤模型，随机分为4组（n=5）,分别为假拉伤组、拉伤组、UII组（胸主动脉球囊拉伤并持续泵入UII 1.0 nmol·kg-1·h-1）和urantide组( 胸主动脉球囊拉伤并持续泵入urantide 10 nmol·kg-1·h-1)。于第21 d取胸主动脉，分别检测血管形态改变、UII表达、平滑肌细胞增殖和胶原表达。结果: ①术后第21 dUII组收缩压高于拉伤组［（140.0±10.0) mmHg vs (132.0±3.4) mmHg, P>0.05］,明显高于urantide 组［（140.0±10.0) mmHg vs (128.0±2.4) mmHg, P<0.05］。②胸主动脉球囊损伤后,损伤血管局部UII表达增强。③同拉伤组比, UII组进一步促进了内膜的增生,管腔面积狭窄率明显增加(0.13±0.05 vs 0.07±0.02, P<0.05);细胞增殖指数明显增加(0.74±0.16 vs 0.40±0.11,P<0.01);胶原表达也明显增加(以IOD计量,318±127 vs 78±26, P<0.01)。④同拉伤组比,urantide组管腔面积狭窄率没有减轻(0.09±0.03 vs 0.07±0.02, P>0.05);细胞增殖指数明显增加(0.73±0.15 vs 0.40±0.11, P<0.01);胶原表达增多但无统计学意义(以IOD计量,200±79 vs 78±26, P>0.05)。结论: 大鼠胸主动脉损伤后局部UII表达增强；外源性UII促进新生内膜平滑肌细胞增殖和胶原表达，加重了损伤血管的狭窄，提示UII参与了损伤后修复的过程；10 nmol·kg-1·h-1urantide不能抑制损伤后血管重塑的进程, 拮抗UII的机制尚有待进一步探讨。     

外周血间充质干细胞移植对球囊损伤兔血管平滑肌细胞凋亡的影响

探讨外周血间充质干细胞(MSCs)移植对模型兔颈动脉球囊成形术后平滑肌细胞凋亡的影响。粒细胞集落刺激因子(G-CSF)动员5 d后采集外周血,用密度梯度离心法结合反复贴壁法分离培养获得纯化的MSCs,以增强型绿色荧光蛋白(GFP)报告基因标记备用。建立兔动脉粥样硬化狭窄模型,随机分为MSCs移植组及对照组,于颈动脉球囊成形术后分别静脉注入MSCs或等体积培养液。术后7、14、28 d取球囊损伤血管标本经TUNEL法(TdT-mediated d-UTP nick end labeling)测定血管平滑肌细胞凋亡率;同时进行归巢MSCs的鉴定;此外,测定术后28 d的内膜、中膜面积,再狭窄率及再内皮化情况。术后7、14、28 d,与对照组比较,移植组平滑肌细胞凋亡率明显增高;仅在移植组血管组织中有GFP阳性细胞分布;术后28 d,移植组内膜面积、内膜中膜面积之比及再狭窄率显著低于对照组,而再内皮化程度则明显优于对照组。静脉移植外周血MSCs能够促进模型兔球囊损伤血管快速内皮化,抑制新内膜增生、减少再狭窄率;这一作用可能与损伤血管局部平滑肌细胞凋亡增加有关。     

Study on Anti-Tumor Effect of Total Glycosides from Radix Paeoniae Rubra in S180 Tumor-Bearing Mice

The objective of the paper was to study the anti-tumor effect of total glycosides from Radix paeoniae rubra in S180 tumor-bearing mice, and to preliminarily explore its mechanism of action. Mice were made into S180 solid tumor model, grouped and administered with the extracts; tumor inhibition rate was measured by harvesting the tumors, and serum IL-2 and IL-4 levels were measured by taking blood samples. Total glycosides of Radix paeoniae rubra significantly inhibited the growth of tumor cells in tumor-bearing organisms, enhanced the cytotoxic activity of NK cells, and increased the serum IL-2 and IL-4 levels. Total glycosides of Radix paeoniae rubra have some anti-tumor effect in vivo, which might have been accomplished through the regulation of the immune system.     

血流切应力变化导致颈总动脉重建及其对血管平滑肌细胞凋亡和分化的影响

目的　探讨动脉血流切应力变化对动脉壁形态结构、零应力状态以及血管平滑肌细胞(vascular smooth muscle cells，VSMC)凋亡和去分化的影响。方法　结扎大鼠左侧颈总动脉的部分分支，使血液全部经由枕动脉流出，造成左颈总动脉(LCA)低血流和低切应力以及对侧右颈总动脉(RCA)高血流和高切应力状态，以假手术不结扎动脉的动物为正常对照。取LCA和RCA，光镜和透射电镜观察血管壁组织形态学变化；测量血管零应力状态下的张开角；TUNNEL法进行原位细胞凋亡检测；免疫印迹法检测VSMC表型分化标志分子hl-calponin的表达。结果　术后7d，低切应力LCA的内径减小了13%左右，壁厚内径比显著增加，张开角显著减小；内皮下层明显增厚，VSMC凋亡数量显著增加，VSMC表型分化标志分子hl-calponin的表达量显著降低。结论　血流切应力显著降低会在短期内引起血管重建，提示VSMC凋亡和去分化可能是低血流和低切应力导致血管重建的早期事件之一。     

瑞舒伐他汀对大鼠颈动脉球囊损伤后细胞凋亡的影响

目的观察瑞舒伐他汀对大鼠颈动脉球囊损伤后细胞凋亡的影响。方法36只雄性SD大鼠随机分为对照组、损伤组和治疗组,每组12只。损伤组和治疗组分别建立大鼠左侧颈动脉球囊损伤模型,右侧颈动脉未予球囊损伤。治疗组于损伤前3d始连续每天给予瑞舒伐他汀5mg／（kg·d）灌胃,对照组和损伤组予9g／L氯化钠溶液灌胃。术后14d取左侧颈总动脉,进行HE染色和末端脱氧核苷酸转移酶介导的生物素-dUTP缺口标记技术（Terminal deoxynucleotidyl transferase biotin—dUTP nick end labeling,TUNEL）的凋亡检测。结果共30只大鼠成功完成本次实验。①血管损伤14d,可见明显的新生内膜;损伤组和治疗组的内膜面积、内膜／中膜面积的比值较对照组增大（P〈0．05）;与损伤组比较,治疗组内膜／中膜面积的比值减少,管腔面积增加26％（P〈0．05）。②对照组血管偶可见单个散在的凋亡细胞;损伤组凋亡细胞阳性率为（12．3±1．8）％,与对照组比较,差异有统计学意义（P〈0．05）;治疗组凋亡细胞数目增多,凋亡细胞阳性率达（26．8±3．2）％,与损伤组比较,差异有统计学意义（P〈0．05）。凋亡细胞主要位于新生内膜。结论瑞舒伐他汀可抑制大鼠颈动脉球囊损伤后的内膜增生,可促进大鼠颈动脉球囊损伤后的细胞凋亡。瑞舒伐他汀促进细胞凋亡的作用可能与其抑制内膜增生有关。     

The Role of Matrix Metalloproteinase-2 in the Remodeling of Cell-Seeded Vascular Constructs Subjected to Cyclic Strain

Tissue engineering offers the opportunity to develop vascular substitutes that mimic the responsive nature of native arteries. A good blood vessel substitute should be able to remodel its matrix in response to mechanical stimulation, as imposed by the hemodynamic environment. We have developed a novel method of studying the influence of mechanical strain on the remodeling of cell-seeded collagen gel blood vessel analogs. We assessed the remodeling capacity by examining the effect of mechanical conditioning upon the expression of enzymes which remodel the extracellular matrix, called matrix metalloproteinases (MMPs), and upon the mechanical properties of the constructs. We found that subjecting collagen constructs to a 10% cyclic radial distention, over a course of 4 days, resulted in an overall increase in the production of MMP-2. Cyclic mechanical strain also stimulated enzymatic activation of latent MMP-2. We found that cyclic strain also significantly increased the mechanical strength and material modulus, as indicated by an increase in circumferential tensile properties of the constructs. These observations suggested that MMP-2-dependent remodeling affects the material properties of vascular tissue analogs. To further investigate this possible connection we examined the effects of dynamic conditioning in the presence of two nonspecific inhibitors of MMP activity. Interestingly, we found that nonspecific inhibition of MMP ablated the benefits of mechanical conditioning upon mechanical properties. Our observations suggest that a better understanding of the complex relation between mechanical stimulation and construct remodeling is key for the proper design of tissue-engineered blood vessel substitutes. © 2001 Biomedical Engineering Society. PAC01: 8719Rr, 8714Ee, 8717-d     

IGF-1 R抗体对血管损伤后新生内膜增生的影响

目的观察胰岛素样生长因子-1(IGF-1)R抗体体内局部干预对动脉粥样硬化大鼠血管损伤后新生内膜增生的抑制作用。方法建立动脉粥样硬化大鼠颈动脉球囊损伤模型,随机分成三组。损伤术后,分别将缓冲液、对照抗体和IGF-1R抗体作用于大鼠损伤血管壁,观察三者对术后不同时期新生内膜增生、细胞增殖的影响,以及对血管平滑肌细胞功能状态的影响。结果经IGF-1R抗体干预后,与给予缓冲液和对照抗体干预相比:各时期内膜/中膜面积比显著降低(P<0.01);损伤后早期,VSMC增殖率明显下降(P<0.01);损伤后期,电镜下可见到较多的凋亡细胞。结论IGF-1R抗体可以抑制损伤后新生内膜增生,减少再狭窄发生率,并可抑制损伤后早期VSMC的增殖。     

组织因子途径抑制物基因局部转染对兔颈总动脉损伤后内膜增生及P53表达的影响

目的研究组织因子途径抑制物(TFPI)基因局部转染对兔颈总动脉损伤处内膜增生及P53表达的影响。方法36只新西兰纯种雄性大白兔颈总动脉损伤后随机分生理盐水组?复制缺陷型腺病毒(AdLacz)组和包载TFPI目的基因复制缺陷型腺病毒(AdTFPI)组。每组12只。术后14d处死动物,取损伤血管进行检测分析。免疫组化染色观察TFPI在转染局部的表达成功;颈总动脉损伤处抽提总RNA,半定量逆转录多聚酶链式反应(RT-PCR)测定P53mRNA表达;同时对颈总动脉病变最明显的取材标本进行HE染色,光学显微镜下观察血管内膜增生,以计算机图像分析系统分析血管内膜?中膜面积和腔面积。结果AdTFPI组家兔的颈总动脉损伤处血管内膜的增生显著受抑制?内膜/中膜面积比值下降;生理盐水组?AdLacz组和AdTFPI组P53mRNA的相对值分别为1.31±0.14、1.27±0.11和4.21±0.87,P53在AdTFPI组表达增强,与前两者相比有显著差异性。结论TFPI基因局部转染显著抑制颈总动脉损伤处血管内膜的增生并增强P53表达。     

MicroRNA 21 Inhibits Left Ventricular Remodeling in the Early Phase of Rat Model with Ischemia-reperfusion Injury by Suppressing Cell Apoptosis

Objective: To determine the role of microRNA 21(miR-21) on left ventricular remodeling of rat heart with ischemia-reperfusion (I/R) injury and to investigate the underlying mechanism of miR-21 mediated myocardium protection.Methods: Rats were randomly divided into three groups: an I/R model group with Ad-GFP (Ad-GFP group), an I/R model group with Ad-miR-21 (Ad-miR-21 group) and a sham-surgery group. Changes in hemodynamic parameters were recorded at 1 week after I/R. Histological diagnosis was achieved by hematoxylin and eosin (H&E). Left ventricular (LV) dimensions, myocardial infarct size, LV/BW, collagen type Ⅰ, type Ⅲ and PCNA positive cells were measured. Primary cultures of neonatal rat cardiac ventricular myocytes were performed and cell ischemic injury was induced by hypoxia in a serum- and glucose-free medium, and reoxygenation (H/R).MiR-21 inhibitor and pre-miR-21 were respectively added to the culture medium for the miR-21 knockdown and for the miR-21 up-regulation. qRT-PCR was used to determine the miR-21 levels in cultured cells. Flow cytometry was performed to examine the cell apoptosis.Results: In the Ad-miR-21 group, LV dimensions, myocardial infarct size, LV/BW, collagen type Ⅰ, type Ⅲ and PCNA positive cells all significantly decreased compared with the Ad-GFP group. At 1 week after I/R, the Ad-miR-21 significantly improved LVSP, LV +dp/dt(max), LV - dp/dt(min), and decreased heart rate (HR) and LVEDP compared with the Ad-GFP group. Compared with the Ad-GFP, the cell apoptotic rate significantly decreased in the Ad-miR-21 group. The miR-21 inhibitor exacerbated cardiac myocyte apoptosis and the pre-miR-21 decreased hypoxia/reoxygenation- induced cardiac myocyte apoptosis.Conclusions: Ad-miR-21 improves LV remodeling and decreases the apoptosis of myocardial cells, suggesting the possible mechanism by which Ad-miR-21 functions in protecting against I/R injury.     

MiR-322-5p Alleviates Cell Injury and Impairment of Cognitive Function in Vascular Dementia by Targeting TSPAN5

PurposeAs the population ages, the incidence of clinical dementia has been rising around the world. It has been reported that microRNAs act as key diagnostic biomarkers and targets for various neurological conditions, including dementia. MiR-322-5p has been revealed to play an important role in multiple diseases. In this study, we aimed to investigate the role and regulatory mechanism of miR-322-5p in vascular dementia.Materials and MethodsIn this study, neonatal rat neurons (NRNs) were subjected to oxygen-glucose deprivation/reoxygenation (OGD/R) to induce cell injury. The animals were subjected to permanent bilateral occlusion of the carotid arteries (2-vessel occlusion, 2VO) to induce the model of chronic brain hypoperfusion.ResultsMiR-322-5p expression was significantly downregulated in the neurons exposed to OGD/R and the hippocampi of 2VO rats. Overexpression of miR-322-5p ameliorated cell apoptosis and the inflammatory response in vitro. In a mechanistic study, miR-322-5p was confirmed to directly target and negatively regulate tetraspanin 5 (TSPAN5) in cultured NRNs. Moreover, overexpression of TSPAN5 could counteract the effects of miR-322-5p overexpression on cell apoptosis and the inflammatory response in OGD/R-treated neurons. More importantly, miR-322-5p improved cognitive ability and inhibited inflammatory production in 2VO rats.ConclusionOverall, the results suggest that miR-322-5p alleviates vascular dementia development by targeting TSPAN5. This discovery may provide a potential therapeutic target for dementia.