论文标题:冠状动脉微血管栓塞对微血管完整性及炎症因子的影响
The Effects of Coronary Microembolization on the Microvascular Function and Cytokine Secretion
论文作者 张庆勇
论文导师 陈君柱；葛均波,论文学位 博士,论文专业 内科学
论文单位 浙江大学,点击次数 64,论文页数 128页File Size16250k
2005-04-20论文网 http://www.lw23.com/lunwen_206848792/ 微血管功能;血管新生;心肌调亡;肥大细胞;炎症因子
Mast cell; Coronary flow reserve; Myocyte apoptosis; Angiogenesis; Cytokine
第一部分 冠状动物微血管栓塞动物模型的建立 目的:建立急性微血管栓塞并可随访的动物模型。 材料、方法:40—50周龄的健康小型猪(巴马系中国)21—25Kg(性别不限)。急性微血管栓塞的模型:一侧股动脉插管,经皮冠状动脉造影后,微栓塞球(购买于美国E-Z Trac公司,白色,直径45.6±7μm)经放置于前降支内的微导管注入,浓度1×10~4个/ml,注射总量累积达15x10~4个。可随访的动物模型,则采用微血管栓塞后的动物经另一侧股动脉插管,应用导管技术复查选择性注射微球后的前降支病变,如冠状动脉血流储备等。术中观察心率及血压的变化。分别于急性微血管栓塞后1天、7天、30天处死动物,分别收集前降支及回旋支血管支配区域的心肌行NBT和H&E染色。 结果:动物处死后,前降支(LAD)支配区域心肌NBT染色见多个缺血或坏死灶,而同样部位心肌组织H&E染色则可清晰的看到微血管内的微栓塞球。而回旋支(LCX)血管支配区域)未见异常。 结论:成功建立了非开胸条件下,经导管冠状动脉急性微血管栓塞并可随访的动物模型。 第二部分 经导管急性微血管栓塞对冠状动脉血流、冠状动脉血流储备及炎症因子的影响 目的:研究急性微血管栓塞中,不同微血栓水平对冠状动脉血流(CBF)、冠状动脉;微血管;微栓塞球;小型猪;动物模型;随访微血管栓塞;冠状动脉血流;血流储备;ET-1;炎症因子
PART ONE The Animal Model of Intracoronary Microembolizationusing Catheterization TechniquesObjective: TO establish a pig model of coronary microembolizaton by use of catheterization techniques.Methods: Miniswines of either sex (20-25 kg body weight) were initially sedated with intramuscular injection of combination ketamine/diazepam (5-10 mg/kg). After endotracheal intubation, anesthesia was maintained by ventilation with 2% isoflurane. Sheaths, Heart rate obtained from the ECG. Intracoronary catheter (Cordis Rapidtransit 3/2.8Fr) was placed (monitored by fluoroscopy) in the proximal left anterior descending (LAD) artery for selective intracoronary infusion of microspheres (Diameter 45μm, 5 000 ml-1, E-Z Trac). Animals were sacrificed post operation 1 day, 7 days, 30 days to assess Hematoxylin & eosin (H&E) staining and nitroblue tetrazolium (NBT) dye as a morphological evidence of miroemolized myocardium.Results: Microspheres in the embolized artery and the inflammatory factors around it with H&E staining. In the embolized areas, a mix of microinfarcted (stained with wihite color and viable tissue could be observed, whereas nonembolized areas were devoid of microinfarctions (staining with blue color) dyed by NBT.Conclusions: Succeed in a pig model of coronary microembolizaton by use of catheterization techniques.Miniswine; Microembolization; Microshpere; Coronary; Animal modelCoronary flow reserve; Coronary blood flow; Endothelin-1; Microembolization; CytokinesObjects: To investigate the cytokines secretion (CME) causes progressive myocytes apoptosis and angiogenesis after coronary microembolization (CME).Methods: We induced CME in 27 miniswines by selective infusion of 15x104 microspheres (45μm) into left anterior descending artery (LAD). At baseline, Day 1 (Dl), 7 (D7) and 30 (D30), we measured 1) coronary sinus levels of IL-8, ET-1, IL-6, TNF-a using radioimmunioassay; 2) IL-6, IL-10, TNF-a, mast cell mRNA using RT-PCR; 3) expression of von-Willebrand factor (vWF) labeling as index of angiogenesis; 4) myocyte apoptosis by TUNEL assay, and 4) MC density using immunohistological staining and ultrastructal study using transmission electron microscopy. Coronary flow reserve (CFR) was assessed by Doppler wire over LAD at Dl, D7, D30 after CME. Four animals with injection of saline to LAD were served as control group.Results: After CME, the number of MCs, level of IL-6, IL-8, ET-1 and TNF (vs. baseline) increased significantly at Dl & D7 D30. Compared to baseline, CFR decreased significantly at Dl after CME but restored to baseline at D7 & D30. However, the number of myocyte apoptosis and angiogenesis increased significantly at Dl & D7 and further elevated at D30. There are significant positive correlations between the number of MCs with LV angiogenesis (r=0.63 with vWF, p<0.01) and myocardial apoptosis (r=0.84, p<0.01). ultrastructural study of mast cell (M) identified that Granules (G) derived from the degranuled-mast cell accumulated in area with collagen (C) and Fibroblast (F) deposition..Conclusions: After CME, MC accumulation is associated with an increase in myocardial level of IL-8 and TNF, angiogenesis and myocyte apoptosis. Despite restoration of CFR by angiogenesis, myocyte apoptosis persisted after CME. These findings suggest that MC play an important role in myocardial injury and repair after CME.
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