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Background and Purpose: According to the WHO (World Health Organization WHO) statistics, in 2010, coronary atherosclerotic heart disease (CHD) death of the total deaths caused by 10% in the first [1] . With percutaneous transluminal coronary balloon angioplasty (PTCA) and percutaneous coronary stent implantation (PCI) is widely used in the treatment of coronary heart disease, the prognosis of patients with coronary heart disease has been significantly improved, mortality was significantly reduced, but PTCA PTCA or PCI, the balloon injury and middle arterial endothelium, causing vascular smooth muscle cells (VSMC) phenotype, migration, proliferation and extracellular matrix synthesis, the formation of neointima, and neointimal formation and proliferation is caused by stent restenosis major pathological changes. Angiotensin Ⅱ (angiotensin Ⅱ, Ang Ⅱ) receptors are mainly two types, namely, Ang Ⅱ 1 receptor that AT1R and Ang Ⅱ 2 receptor that AT2R. Ang Ⅱ AT1 receptor activation can play vasoconstrictor, promoting cell proliferation and migration, to promote neointimal formation, extracellular matrix deposition, trigger inflammation, thrombosis and oxidative stress effect, these are the restenosis process of the main factors world. AT2 receptor activation is played vasodilatory, anti-proliferative antithrombotic, induce apoptosis and production of nitric oxide NO effect. Therefore we choose angiotensin Ⅱ 2 type 1 receptor gene (ang Ⅱ type 2 receptor gene, AT2R gene) as a target to observe its effect on restenosis, neointimal proliferation after. Gene transfer in vivo (in vivo) is the target gene directly into cells of the lesion, the expression of the gene in situ therapeutic effect. Is the most direct method of gene therapy. However, it is difficult to present difficulties mainly target gene expression into the vascular locally and effectively. Now commonly used vector-mediated gene transfection, gene vectors are commonly used viral vectors (such as adenovirus vectors, retroviral vectors) and non-viral vectors (such as a plasmid vector, liposome) carriers, both genes from the ideal carriers have a certain gap. Adenovirus toxicity and immunogenicity clinical application is limited so. Also found that adenovirus vectors for atherosclerotic lesions transfection rate, while other arteries were transfected with increased risk. And people generally have immunity to the virus, viral vectors susceptible host immune system clears the resulting gene expression in a short time. Non-viral vector plasmid DNA as a representative. Its main advantage is gene-carrying unlimited size, are unlikely to cause the host cells of the immune response, do not integrate into the host cell DNA, transfection efficiency disadvantage is low, especially in the living tissue, expressed locally lower rate of transfection. The 1960s and 1970s, people began to study electroporation-mediated gene transfection, cells in the electric field reversible or irreversible membrane perforation occurs, these channels can help genetic molecules into cells, a large number of studies have confirmed [4,5] , electroporation method can enhance the effect of gene transfection, gene expression and increase the time. However, the method used for in vitro cultured cells in living tissue is seldom used, and access to a large literature after electroporation in vivo vascular studies is relatively small, this study will electroporation method for in-vivo vascular tissue in order to achieve increased AT2R Local overexpression of vascular purposes, thereby AT2R expression was observed in rats after vascular injury neointimal influence. Methods: 1. Plasmid as a template to pUHD-10.3/AT2R, PCR amplification of full-length cDNA sequences AT2R, and then cloned into the vector pEGFP2-N2, construct its eukaryotic expression vector pEGFP-N2/AT2R. (2) made of electroporation for blood vessel clip-shaped electrode sheet and in vivo electroporation instrument preparation. 3.PTCA balloon injury in animal models of restenosis was constructed by pulsed field-mediated pEGFP-AT2R or pEGFP-N2 in the rat carotid artery intima local expression. 4 Immunohistochemical staining was detected in the rat carotid artery AT2R endometrium 5.RT-PCR to detect AT2R mRNA in the rat carotid artery AT2R expression 6.HE staining neck injury in rats expressing total Impact of arterial neointimal results: 1.pEGFP-N2/AT2R successfully constructed by sequencing and gene pool entirely consistent. 2 homemade clip-shaped pads can be used for electroporation-mediated AT2R recombinant eukaryotic expression plasmid in vivo transfection. 3.PTCA balloon injury law can successfully build an animal model of restenosis. 4 immunohistochemistry results suggest that pulsed electric field can effectively mediate AT2R in rat carotid artery intima expression, electroporation transfection group of carotid artery intima AT2R expression level was significantly higher than simple injury, idling group and no electric field transfection group (P lt; 0. 01), 7d, and kept strong expression, 14d after the rapid decline, 21d, expressed almost disappeared. 5.RT-PCR results suggest that pulsed electric field can effectively mediate AT2R in rat carotid artery intima-expression, electroporation transfection group of carotid artery intima AT2R expression levels were significantly higher in groups with and without idling farm transfection group (P lt; 0. 01), 7d, and kept strong expression, 14d and reached a peak after the rapid decline, 21d when weakly expressed. 6.HE staining results suggest that: 21 d transfection, the transfected group intimal area and medial area ratio was significantly lower than simple injury and idling group [(0.76 ± 0.08), (1.39 ± 0.08), Research findings; 1. PTCA balloon injury law can successfully build an animal model of restenosis, the use of home-made electrode can be successfully mediated vascular AT2R gene in rat carotid arterial wall expressed; 2. AT2R gene transfection can effectively inhibition of rat carotid artery after balloon injury intimal smooth muscle cell proliferation, proliferation, thereby inhibiting neointimal hyperplasia.
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