DR和CT对大鼠股动脉结扎诱导的侧支血管显像能力的对比研究

目的:探讨数字化X线摄影(digital radiography,DR)和电子计算机断层扫描成像(Computed Tomography,CT)对大鼠股动脉结扎诱导的侧支血管显像能力的对比.方法:28只健康SD大鼠,右侧行股动脉结扎,存活1W,采用明胶-四氧化三铅混合物行血管造影观察大鼠后肢侧支血管形成情况并分别采用DR及CT进行摄片,观察DR及CT对侧支血管的显像能力.结果:DR及CT均显示在股动脉结扎处血管连续性中断,并出现不同数量的侧支血管;DR对新生侧支血管的显影分辨率和清晰度明显高于CT,且远端股动脉显影较CT清晰,CT横断面成像具有放射状伪影.结论:经DR拍摄的侧支血管的显像能力较CT清晰,利用DR可以直观清晰的将其显像.     

白藜芦醇促进老年大鼠缺血后肢侧支血管生长

目的 本研究旨在探讨白藜芦醇对老年大鼠缺血后肢侧支血管生长的影响。方法 采用老年大鼠股动脉结扎建立侧支血管生长模型,10 mg/kg白藜芦醇处理,免疫荧光染色和HE染色观察大鼠后肢侧支血管生长情况。结果 HE染色显示,股动脉结扎后给予白藜芦醇处理使侧支血管管壁增厚,管腔增大;免疫荧光染色显示,股动脉结扎后给予白藜芦醇处理使侧支血管管壁增殖细胞（Ki-67阳性细胞）增多,eNOS表达增强。结论 白藜芦醇可促进老年大鼠缺血后肢侧支血管的生长。     

兔后肢缺血诱导侧支血管生长过程中巨噬细胞浸润的变化

目的检测兔侧支血管生长过程中各时期巨噬细胞的浸润情况;方法单侧结扎兔后肢股动脉,随后将股动脉结扎的远侧端连到相邻的静脉上造成动静脉短路,另侧为对照组,分别存活2d,1周,2周,4周后处死,用特异性的巨噬细胞抗体(RAM11)免疫荧光组织化学结合共聚焦技术检测侧支血管壁内巨噬细胞的数目及其分布;结果在正常血管,其外膜有少量巨噬细胞的存在,股动脉结扎后2d,侧支血管外膜巨噬细胞的数目增加,并黏附至内皮细胞,结扎1周后,侧支血管外膜巨噬细胞的数目显著增加,中膜有巨噬细胞的浸润,结扎2周后,侧支血管外膜巨噬细胞的数目减少,但仍高于正常血管,结扎4周后,侧支血管巨噬细胞的数目明显减少,跟正常血管情况类似,统计学分析结果表明,在结扎后2d、一周、二周和四周不同的时间,巨噬细胞在侧支血管的分布差异具有显著性;结论侧支血管发育过程中巨噬细胞的浸润和侧支血管的形成密切相关,提示巨噬细胞参与了侧支血管的生长发育。     

经桡动脉介入治疗老年急性冠脉综合征的应用研究

目的观察老年急性冠脉综合征（ACS）经桡动脉途径介入治疗（TRI）的可行性和安全性以及近期疗效及并发症发生情况。方法选择2010年2月-2011年8月在我院住院经桡动脉穿刺行经皮冠状动脉介入治疗（PCI）的急性冠脉综合征老年患者（年龄70岁以上）50例,与同期住院年龄70岁以上经股动脉行PCI治疗的52患者进行观察比较治疗效果以及并发症及近期预后。结果桡动脉组（观察组）50例中,对其中62支病变血管进行TRI,TRI成功率为97．2％;股动脉组（对照组）52例,对其种63支病变血管进行PCI,成功率为97．5％。观察组无桡动脉闭塞及其他并发症。结论老年急性冠脉综合征（ACS）的PCI治疗中,经桡动脉穿刺途径与经股动脉穿刺途径相比,两者有相同的治疗效果,但经桡动脉穿刺途径治疗术后与穿刺有关的并发症较股动脉路径明显减少,患者术后体位及活动不受限制,术后护理工作量小,尤其适合较为肥胖的老年患者,值得临床推广应用。     

兔后肢动静脉短路诱导动脉生成过程中VEGF(A)及其受体Flk-1的表达

目的探讨兔后肢动脉生成过程中VEGF(A)及其受体Flk-1的表达特征。方法兔双侧股动脉结扎,并将一侧结扎的股动脉远侧端缝到伴行的静脉上造成动静脉短路,另一侧为对照组。一周后动物被处死。应用免疫荧光组织化学技术检测侧支血管中VEGF(A)及其受体Flk-1的表达。结果在正常血管,VEGF(A)没有表达,Flk-1只在内皮细胞上有微弱表达;对照侧,VEGF(A)和Flk-1在平滑肌细胞和内皮细胞的表达明显上调;在动静脉短路侧,VEGF(A)和Flk-1的表达显著增加,分别是对照侧的2·3倍和2倍。结论在侧支血管发育过程中,VEGF(A)及其受体Flk-1在平滑肌细胞和内皮细胞同时表达上调,在快速生长的侧支血管它们的表达更为显著,提示Flk-1的表达在VEGF促动脉生成作用中具有重要意义。     

CT血管成像后处理技术在肠系膜血管栓塞诊断中的应用

目的探讨CT血管成像（CT Angiography,CTA）后处理技术在肠系膜血管栓塞诊断中的应用价值。方法50例肠系膜血管栓塞患者,均行螺旋CT增强扫描,原始数据采用多平面重组（MPR）、容积成像（VR）和最大密度投影（MIP）方法进行后处理,观察其对明确诊断所起的作用。结果MPR、VR和MIP方法均能显示病变,以MPR显示率最高,结合3种方法可以获得明确诊断。结论CTA能够明确肠系膜血管栓塞的诊断,MPR进行图像后处理的价值最大。     

股动脉注射蝮蛇抗栓酶等治疗血栓闭塞性脉管炎67例

６７例血栓闭塞性脉管炎患者从股动脉注射药物,观察其疗效。方法采用蝮蛇抗拴酶０．７５ＩＵ、６５４－２１０ｍｇ,妥拉苏林２５ｍｇ、１％普鲁卡因２０ｍｌ行患侧股动脉注射治疗１５天,治疗前后对患侧足背动脉、胫后动脉、月国动脉、股动脉共２７６条血管分别用经颅多普勒血流仪（ＴＣＤ）检查。结果治疗后患肢动脉血流峰值明显增高,搏动指数（ＰＩ）和阻力指数（ＲＩ）明显降低,临床表现明显好转。     

64排CT血管造影在脑动静脉畸形诊断中的价值

目的：探讨64排CT血管造影（computedtomography angiographycTA）对脑动静脉畸形（cerebral arefiovenousmalformation,AVM）的诊断价值。方法：16例AVM患者,均行64排螺旋CT血管造影检查,使用多种重建方法,由两名有经验的医生对畸形血管团进行分析。结果：16例均为单发瘤巢,16例AVM均显示了大小不等的畸形血管团及供血动脉和引流静脉,其中,2例同时伴脑出血（12．5％）,3例有出血后软化灶形成（18．75％）,16例发现有供血动脉31支,16例发现有明确的引流静脉21支。结论：64排CTA安全．快速．结合多种重建方法．可以清晰显示AVM的供血动脉、瘤巢．引流静脉．为临床治疗提供了可靠的信息．     

冠脉护理在320排螺旋CT冠状动脉造影中提高图像质量的作用

目的：探讨320排螺旋CT心脏冠状动脉护理的作用及其临床意义。方法：2009年11月至2010年3月,于我院行心脏检查1024例行320排螺旋CT冠状动脉造影检查的患者,检查前对每一患者进行心理辅导,减轻紧张情绪;进行心率控制、屏气训练等护理措施准备;在扫描过程中配合影像技师使用高压注射器;检查完成后积极与患者交谈,严密观察患者状态,预防造影剂不良反应的发生。结果：受检患者中987例患者顺利完成检查,图像重建后血管显示效果优;16例血管显示良;有1例患者造影剂未全部进入血管内,导致血管显影不充分。有2例出现轻度过敏反应;无空气栓塞或任何心脑血管意外的发生。受检病例中432例同时进行了冠状动脉造影,98%（425/432）与检查结果完全一致,有2%（8/432）与检查结果有轻度误差。结论：检查前细致的护理对提高心脏冠状动脉血管成像成功率、提高至关重要。     

三维高分辨率磁共振血管壁成像对脑梗死患者血管狭窄的诊断价值分析

目的：探讨三维高分辨率磁共振血管壁成像（HR-MRI VWI）对脑梗死患者血管狭窄的诊断价值。方法：回顾性收集2022年1月至2022年10月于广州市中西医结合医院治疗的196例脑梗死患者的临床资料,所有患者均行HR-MRI VWI和数字减影血管造影（DSA）检查。记录脑梗死患者HR-MRI VWI成像特征,以DSA为金标准,Kappa检验HR-MRI VWI与DSA检出病变血管部位、血管狭窄程度的一致性。受试者工作特征（ROC）曲线分析HR-MRI VWI诊断脑梗死血管狭窄程度的价值。结果：HR-MRI VWI可检测到脑梗死病变血管区域皮层下梗死以及同侧病变血管内斑块,斑块HR-MRI VWI成像特征为斑块增强、阳性壁重塑、斑块T1高强度和斑块表面不规则,平均斑块负荷（75.09±12.13）%。DSA检出病变血管223支,HR-MRI VWI检出病变血管212支。HR-MRI VWI与DSA检出病变血管部位、血管狭窄程度一致性良好（Kappa值=0.802、0.775,P<0.05）。HR-MRI VWI鉴别诊断脑梗死血管狭窄Ⅲ～Ⅳ级的曲线下面积为0.942,灵敏度为94.9...     

营养动脉结扎和液氮冷冻对股骨头内局部氧分压的影响

目的：观察营养动脉结扎和液氮冷冻对股骨头内局部氧分压的影响,为后期制作极度低氧股骨头缺血坏死模型打下基础。方法：9只雄性大耳白兔随机平均分为对照组、液氮冷冻组和动脉结扎＋液氮冷冻组,对照组动物不做任何处理,液氮冷冻组动物行股骨头液氮冷冻使其发生缺血坏死,动脉结扎＋液氮冷冻组动物先结扎旋股内外侧动脉,再对股骨头进行液氮冷冻。造模后立刻活体观察股骨头内氧分压变化。结果：液氮冷冻组股骨头内氧分压较对照组下降一半左右,2组比较有显著性差异（P〈0．05）;动脉结扎＋液氮冷冻组动物股骨头内氧分压进一步下降到对照组的1／8左右,与其他2组相比有显著性差异（P〈0．05）。结论：液氮冷冻和旋股内、外侧动脉结扎均可明显降低股骨头内氧分压,两者合用具有重叠效应,可共同促使股骨头内氧分压下降。     

Collateral vessel growth induced by femoral artery ligature is impaired by denervation

Innervation plays an important role in development and remodeling of blood vessels. However, very little is known whether innervation is involved in arteriogenesis. In the present study, we tested the hypothesis that innervation may contribute to the process of arteriogenesis induced by ligature of femoral artery in rat/rabbit hind limb with or without denervation. We found that: (1) angiography showed more collateral vessels in the ligature side than that in ligature plus denervation side; (2) collateral vessels in denervation side was characterized by an inward remodeling; (3) in both collateral vessels (CVs) from only femoral ligature side as well as the ligature plus denervation side, ICAM-1 and VCAM-1 expression was up-regulated but increased VCAM-1 was more evident in the adventitia of collateral vessels of only femoral ligature side; (4) 7 days after surgery, in CVs from the femoral ligature side only, numerous macrophages (RAM11 positive cells) and high cell proliferation ratio (ki67 positive cells) were detected, but they were less in the denervation side. In conclusion, our data demonstrate for the first time that neural regulation is one of the factors that contributes to collateral vessel growth in rat/rabbit hind limb ischemic model by showing collateral vessel growth induced by femoral artery ligature is impaired by denervation.     

The role of the pericytes of the adventitial microcirculation in the arterial intimal thickening

Segments of rat femoral arteries, with one collateral each, occluded between ligatures and dissected from surrounding tissue, developed intimal thickening, with or without ligation of their collaterals. Numerous newly-formed capillaries from the surrounding arterial microcirculation growing into the adventitia, tunica media and intimal thickening were demonstrated by means of serial longitudinal sections, predominantly in the ostium of the collateral. When the ligatures were applied without damaging the microcirculation surrounding the artery and the normal continuity of the adventitial vessels was unchanged, earlier presence of intimal thickening was observed. When the fibrous layers of the adventitia were removed at the moment of the arterial ligation, the continuity between newly-formed vessels of the neoadventitia and those growing into the media and neointima was much more evident. It was then noted that the pericytes constituted a major component of the intimal thickening. The introduction of contrast material in microcirculation confirmed the connections between newly-formed adventitial and intimal vessels. At the beginning of the experiment, autoradiographic studies showed an increased DNA synthesis in the cells of preformed postcapillary venules and capillaries of surrounding arterial microcirculation and later in those of the newly-formed vessels growing into the arterial wall. These results indicate that newly-formed capillaries derived from surrounding arterial microcirculation penetrate the wall of the occluded arterial segments and contribute to the intimal thickening formation. It is likely that the pericytes and endothelial cells (EC) of these ingrowing vessels are sources of myointimal cells at the intimal thickening and of endothelium at the luminal surface, respectively.     

Characteristics of development of collateral vessels after experimental ligation of the femoral artery under conditions of venous insufficiency

Isolated ligation of the femoral artery and its combined ligation with the vein was performed in experiments on 62 dogs. Anatomical and physiological methods were used. It was stated that at the combined ligation collaterals developed sooner, number of anastomoses in muscles of the femoral posterior osseous-fascial case was greater, and their lumen was wider than at the isolated ligation of the femoral artery. However, the combined arterio-venous insufficiency was followed by a more severe postoperative course and noticeable biochemical disturbances. Thus, a certain discrepancy between the development of collaterals and the function of the tissue they feed was revealed. Analysing the data obtained it is possible to conclude that venous insufficiency, despite accelerating the transformation of the collaterals as a whole, aggravates conditions for collateral arterial circulation in the extremity.     

Blood monocyte concentration is critical for enhancement of collateral artery growth

Arteriogenesis has been associated with the presence of monocytes/macrophages within the collateral vessel wall. We tested the hypothesis that arteriogenesis is functionally linked to the concentration of circulating blood monocytes. Monocyte concentrations in peripheral blood were manipulated by single injections of the antimetabolite 5-fluorouracil (5-FU), resulting in a marked rebound effect in New Zealand White rabbits. Collateral artery growth was assessed by the use of a model of acute femoral artery ligation. Seven days after ligation, collateral conductance and the number of visible collateral arteries were increased in the rebound group. This increase was accompanied by an increased monocyte accumulation as demonstrated by immunohistology in the thigh 3 days after surgery. In a second animal model (129S2/SvHsd mice), 5-FU treatment caused a remarkable decrease in blood monocyte numbers at day 4, followed by a rebound effect at day 12. Foot blood flow, assessed by laser-Doppler imaging before and at various time points after surgery, increased from day 7 through day 21 in mice from the rebound group. In contrast, ligation during the phase of monocyte depletion resulted in a reduction of blood flow reconstitution. This inhibition could be reversed by an injection of isolated monocytes. In conclusion, we have demonstrated a functional link between the monocyte concentration in the peripheral blood and the enhancement of arteriogenesis.     

Shear induced collateral artery growth modulated by endoglin but not by ALK1

Transforming growth factor-beta (TGF-β) stimulates both ischaemia induced angiogenesis and shear stress induced arteriogenesis by signalling through different receptors. How these receptors are involved in both these processes of blood flow recovery is not entirely clear. In this study the role of TGF-β receptors 1 and endoglin is assessed in neovascularization in mice. Unilateral femoral artery ligation was performed in mice heterozygous for either endoglin or ALK1 and in littermate controls. Compared with littermate controls, blood flow recovery, monitored by laser Doppler perfusion imaging, was significantly hampered by maximal 40% in endoglin heterozygous mice and by maximal 49% in ALK1 heterozygous mice. Collateral artery size was significantly reduced in endoglin heterozygous mice compared with controls but not in ALK1 heterozygous mice. Capillary density in ischaemic calf muscles was unaffected, but capillaries from endoglin and ALK1 heterozygous mice were significantly larger when compared with controls. To provide mechanistic evidence for the differential role of endoglin and ALK1 in shear induced or ischaemia induced neovascularization, murine endothelial cells were exposed to shear stress in vitro. This induced increased levels of endoglin mRNA but not ALK1. In this study it is demonstrated that both endoglin and ALK1 facilitate blood flow recovery. Importantly, endoglin contributes to both shear induced collateral artery growth and to ischaemia induced angiogenesis, whereas ALK1 is only involved in ischaemia induced angiogenesis.     

Local Delivery of Polarized Macrophages Improves Reperfusion Recovery in a Mouse Hind Limb Ischemia Model

Aims

Enhancement of collateral development in coronary or peripheral artery disease is a therapeutic target, but it has proven difficult to achieve. Macrophages are key players in collateral remodeling, yet the effect of different macrophage subsets on arteriogenesis has not been investigated.

Methods and Results

Murine macrophages were cultured from bone marrow and polarized into M1 (IFNγ), M2a (IL-4) or M2c (IL-10) subsets. C57BL/6 mice underwent femoral artery ligation followed by intramuscular injection of macrophage subsets. Using eGFP expressing macrophages, cells could be detected at least 6 days after ligation and were located in the perivascular space of collateral vessels. After 14 days, perfusion ratio was increased in animals treated with M1 as well as M2a and M2c macrophages compared to control. Depletion of circulating monocytes by clodronate liposome injections did not hamper reperfusion recovery, however, treatment with exogenous polarized macrophages improved perfusion ratio after 14 days again. We used IL10R^fl/fl/LysMCre⁺ mice to study the effect of inhibition of endogenous polarization towards specifically M2c macrophages on arteriogenesis. Deletion of the IL10-receptor (IL10R) in the myeloid lineage did not affect reperfusion recovery, yet the pro-arteriogenic effect of exogenously injected M2c macrophages was still present.

Conclusions

Local injection of polarized macrophages promotes reperfusion recovery after femoral artery ligation and is not influenced by depletion of circulatory monocytes. Preventing endogenous M2c polarization did not affect reperfusion recovery suggesting that M2c’s are not required for collateralization, but are sufficient to induce collateral formation upon exogenous administration. This is the first study using local injection of macrophage subsets showing the pro-arteriogenic effect of polarized macrophages.     

Activation of the integrins α5β1 and αvβ3 and focal adhesion kinase (FAK) during arteriogenesis

Migration and proliferation of smooth muscle cells (SMC) are important events during arteriogenesis, but the underlying mechanism is still only partially understood. The present study investigates the expression of integrins alpha 5 beta 1 and v beta 3 as well as focal adhesion kinase (FAK) and phosphorylated FAK (pY397), key mediators for cell migration and proliferation, in collateral vessels (CV) in rabbit hind limbs induced by femoral ligation or an arteriovenous (AV) shunt created between the distal femoral artery stump and the accompanying femoral vein by confocal immunofluorescence. In addition, the effect of the extracellular matrix components fibronectin (FN), laminin (LN), and Matrigel on expression of these focal adhesion molecules proliferation was studied in cultured SMCs. We found that: (1) in normal vessels (NV), both integrins alpha 5 beta 1 and alpha v beta 3 were mainly expressed in endothelial cells, very weak in smooth muscle cells (SMC); (2) in CVs, both alpha 5 beta 1 and alpha v beta 3 were significantly upregulated (P < 0.05); this was more evident in the shunt-side CVs, 1.5 and 1.3 times higher than that in the ligation side, respectively; (3) FAK and FAK(py397) were expressed in NVs and CVs in a similar profile as was alpha 5 beta 1 and alpha v beta 3; (4) in vitro SMCs cultured on fibronectin (overexpressed in collaterals) expressed higher levels of FAK, FAK (pY397), alpha 5 beta 1, and alpha v beta 3 than on laminin, whereas SMCs growing inside Matrigel expressed little of these proteins and showed no proliferation. In conclusion, our data demonstrate for the first time that the integrin-FAK signaling axis is activated in collateral vessels and that altered expression of FN and LN may play a crucial role in mediating the integrin-FAK signaling pathway activation. These findings explain a large part of the positive remodeling that collateral vessels undergo under the influence of high fluid shear stress.     

The ankyrin repeat containing SOCS box protein 5: a novel protein associated with arteriogenesis

Arteriogenesis, the growth of pre-existing collateral arteries, can be induced in rabbit by occlusion of the femoral artery. In order to identify and characterize genes differentially expressed during the early phase of arteriogenesis, cDNA of collateral arteries 24h after femoral ligation or sham operation was subjected to suppression subtractive hybridization. We identified the ankyrin repeat containing SOCS box protein 5 (asb5) and cloned the rabbit full-length cDNA. Asb5 was demonstrated to be a single-copy gene. We localized the asb5 protein in vivo in endothelial and smooth muscle cells of collateral arteries as well as in satellite cells. Asb5 was significantly upregulated in growing collateral arteries on mRNA and protein level. The infusion of doxorubicin in rabbit led to a significant decrease of the asb5 mRNA. In summary, our data show that asb5 is a novel protein implicated in the initiation of arteriogenesis.