The Experiemental Study On The Relationship Between The Adventitia Cell And Restenosis Postangioplasty

One of the most important problems needed to be solved rapidly is the high rate of restenosis after angioplasty. The migration of vascular smooth muscular cell is regarded as the main factor contributing to the thick neointimal mass for the restenosis mechanism. However, the recent study reported that the adventitia is related to the formation of vascular restenosis after angioplasty, becase of fibroblast migration from the adventitia into the intima. But there is still a query whether adventitial cell migration exists, the mechanism, however, is unknown even if the cellular migratory event is ture. In this study, an improved stenostic model of rat carotid artery was set up with guidewire instead of balloon; and then the adventitial cell was labeled and its translocation was traced in the injuried artery, aiming at verifying fibroblast migration from adventitia into neointima; and determinate the correlation between adventitial cell and restenosis. Confirm that adventitial fibroblast could express the beta receptor of the platelet-derived growth factor(PDGFR-(3) from the gene level, therafter synthesis the PDGFR-P antisense oligodeoxynucleotides(A-ODN) in order to inhibit the expression of PDGFR-p and adventitial cell migration ,and investigate the migrating mechanism of adventitial cell, so to provide a new way for prevention and therapy postangioplasty restenosis.Part IThe Restenosis Model Study in Rat Carotid Artery : Comparison the Restenosis set up by Modified Guidewire with that by BalloonPurpose: To build an optimal stenostic model of postangioplasty by the modified with guidewire instead of balloon.Materials and Methods: After two kinds of stenostic models were made with guidewire and balloon respectively. The pathological changes of models were observed at different times with DSA, MRI, light microscope and image analysis system ,and then the experimental cost successful rate, bleeding volume, mortality and experimental efficiency were compared between methods.Results: 1.Image results: DSA and MRA showed that carotid arteries injuried by guidewire developed continuous and symmetric stenosis of artery, reversely, intermittent and asymmetrical stenosis by balloon, even blocked. 2. Light microscope: Two methods resulted in the similar pathological changes of injuryed artery such as intima denudation ,media laceration , early thrombosis, adventitia and neointima thickening, and narrowing. 3. Image analysis system : there are no significant difference (P>0. 05) in adventitial area, intimal area, vascular cavaarea and rate of stenosis; However, between two methods of making model at different time, experimental cost ,successful rate , bleeding volume, mortality and experimental efficiency were.significant (P<0. 05) .Conclusion: The guidewire is identified to balloon in making restenosis model of angioplasty; however, the former is superior to the later in simplifying experimental procedures, successful rate, decreasing morality, reducing experimental cost and increasing efficiency. The first method may completely replace the second in setting up the stenostic model of rat carotid artery .Part II The Study on the Relation of the Adventitial Cell Migration with RestenosisPostangiolastyPurpose: To verify on protein level fibroblasts translocation from adventitia into neointima by labeling adventitia cells with bromodeoxyuridine(BrDU), and explore the relationship of adventitial fibroblast with restenosis .Materials and methods: After injurying adventitia directly with mechanical method and intima with guidewire , fibroblasts were labeled with BrDU , and cells' dynamic distribution in adventitia was observed, media and neoitima at different times(3d, 7d, 14d and 28d) by means of single-double-label immunohistochemistry, light microscope, electronic microscope and image analysis system.Results: 1.Immunohistochemistry : more adventitial fibroblasts combined with BrDU could be found in adventitia on 3rd day postangioplasty, and the number of this kind of cells reached the mo...