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BACKGROUND:Vascular endothelial growth factor(VEGF)can promote vascular endothelial regeneration,inhibit thrombosis,and attenuate neonatal intimal thickness and luminal stenosis degree.OBJECTIVE:The present study established atherosclerosis models in rabbits and observed the effects of local transfection of VEGF gene on restenosis after angioplasty.DESIGN,TIME AND SETTING:A randomized controlled animal experiment was performed at the Laboratory of Microorganism,Tongji Medical College,Huazhong University of Science and Technology between November 2004 and December 2006.MATERIALS:Rabbits were daily raised with high-fat diet to create atherosclerosis models.Twenty successful rabbit models were randomly and evenly divided into a control group and a gene treatment group.METHODS:The DcNDA 3.0 recombinant human VEGF165(hVEGF 165)was trimsferred to the ventral aorta through the use of Foley's catheters.and the pcDNA3.0 was transfefred in the controls.MAIN OUTCOME MEASURES:At 1,2,and 4 weeks after surgery,luminal area of left renal artery opening was measured by MRI.At 2 and 4 weeks after surgery,the ratio for intimal to medial area was obtained through the use of HMIAS-2000 high definition color medical image analysis software.Simultaneously,vascular endothelial cell regeneration was observed by immunohistochemistry of factor Ⅷ related antigen.RESULTS:The pcDNA3.0/hVEGF 165 could be successfully transferred through the use of Foley's catheters.At 2 and 4 weeks after surgery,luminal area was larger in the gene treatment group than in the control group(P<0.01);simultaneously, the ratio of intimal to medial area was significantly smaller in the gene treatment group than in the control group(P<0.05).In the gene treatment group,expanded vascular endothelial cell regeneration was accomplished at 2 weeks after surgery,while in the control group,it took 4 weeks.CONCLUSION:pcDNA3.0/hVEGF 165 gene transduction can promote local vascular endotllelialization and apparently attenuate restenosis degree and intiaml thickening.
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This study evaluated the effects of adenovirus vector mediated human vascular endothelial growth factor-165 (hVEGF165) gene on prevention of restenosis after angioplasty. Rabbit models of bilateral carotid artery injury were established by balloon denudation. The recombinant adenoviruses containing hVEGF165 cDNA was directly injected into left side of the injured carotid arteries. On day 3 and week 3 after transfection the expression of VEGF was observed by RT-PCR and immunohistochemistry. The thrombokinesis, reendothelialization (rET) and intimal hyperplasia in carotid arteries were evaluated by computerized image analysis system 3 weeks after gene transfer. The changes in the VEGF gene-treated side were compared with the control side. Our results showed that 3 days and 3 weeks after hVEGF165 gene transfer the VEGF mRNA and antigen expression were detected in vivo. 3 weeks after the transfer, the carotid artery rET was markedly better in the VEGF gene-treated group compared with the control. The thrombokinesis, intima area/media area (I/M), maximal intimal and medial thicknesses (ITmax and MTmax) demonstrated a statistically significant decrease in arteries treated with VEGF gene as compared with the control group. It is concluded that VEGF gene transfer could be achieved by intra-arterial injection of recombinant adenoviruses. It might accelerate the restoration of endothelial integrity, inhibit thrombokinesis and attenuate intimal hyperplasia in the injured arteries after VEGF gene transfer. This procedure could be useful in preventing restenosis after angioplasty.
Assuntos
Animais , Masculino , Coelhos , Adenoviridae , Genética , Metabolismo , Angioplastia com Balão , Lesões das Artérias Carótidas , Patologia , Estenose das Carótidas , Divisão Celular , Endotélio Vascular , Ferimentos e Lesões , Patologia , Terapia Genética , Hiperplasia , Músculo Liso Vascular , Biologia Celular , RNA Mensageiro , Genética , Recombinação Genética , Transfecção , Métodos , Fator A de Crescimento do Endotélio Vascular , GenéticaRESUMO
To evaluate the protective effect of puerarin on ischemic myocardium in dogs with acute myocardial infarction (AMI) and to reveal its possible mechanism, 10 dogs were randomly divided into puerarin group (group G) and control group (group C). AMI model was established in all dogs. Puerarin or saline was administered over a period of 21 days. Coronary angiography was performed before and after ligation of coronary artery. Eight hemorheological parameters were examined before and 22 days after the operation. The infarct area and vessel density of myocardium were assessed. The infarct area in group G was smaller than that in group C. Angiography 2 h and 22 d after ligation of coronary artery revealed significant augmentation of collateral vessels in group G as compared with control group. The platelet aggregation and the blood viscosity were increased during AMI when compared with control phase, and the increased indexes during AMI would be inhibited when puerarin were given. Capillaries and distribution vessel density in ischemic zone on day 22 showed statistically significant augmentation in group G as compared with control group. Puerarin might improve the opening and formation of coronary collateral circulation, and might inhibit the increase of platelet aggregation and the blood viscosity during AMI,and thereby improve microcirculation and restrict myocardial infarct area.
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To evaluate the protective effect of puerarin on ischemic myocardium in dogs with acute myocardial infarction (AMI) and to reveal its possible mechanism, 10 dogs were randomly divided into puerarin group (group G) and control group (group C). AMI model was established in all dogs. Puerarin or saline was administered over a period of 21 days. Coronary angiography was performed before and after ligation of coronary artery. Eight hemorheological parameters were examined before and 22 days after the operation. The infarct area and vessel density of myocardium were assessed. The infarct area in group G was smaller than that in group C. Angiography 2 h and 22 d after ligation of coronary artery revealed significant augmentation of collateral vessels in group G as compared with control group. The platelet aggregation and the blood viscosity were increased during AMI when compared with control phase, and the increased indexes during AMI would be inhibited when puerarin were given. Capillaries and distribution vessel density in ischemic zone on day 22 showed statistically significant augmentation in group G as compared with control group. Puerarin might improve the opening and formation of coronary collateral circulation, and might inhibit the increase of platelet aggregation and the blood viscosity during AMI,and thereby improve microcirculation and restrict myocardial infarct area.
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AIM: To investigate the role of nitric oxide in proliferation and secretion of vascular endothelial cells induced by vascular endothelial growth factorr (VEGF). METHODS: The in vitro cultured vascular endothelial cells of rabbit aorta were divided into control group, VEGF-treated group and VEGF+L-NAME treated group, the absorbance (A) value of vascular endothelial cells, endothelin-1(ET-1) and von Willebrand factor (vWF) in the supernatant were examined by WST-1 assay, radioimmunoassay and ELISA. RESULTS: The A value in VEGF and VEGF+L-NAME treated group were higher than that in control group (P