Abstract:

Abstract:Objective To investigate the influence of the recombinant plasmid Psilencer1.0-U6-siRNA-stat3  on neointima formation of vein graft and develop a new way to prevent restenosis of the vessel graft after arterial bypass. Methods 40 Wistar rats were divided into 2 groups(n=20):  experiment group and control group.The recombinant plasmid Psilencer1.0-U6-siRNA-stat3  (exeperiment group) and scramble plasmid (control group) were combined with the liposomes Lipofectimine 2000 and were transfected into vein graft mediated by bioprotain gel via adventitia.On day 3，7，14，28，the vein graft interposed into the arterilized environment were extracted after irrigating 4% formaldehyde through left ventricle in 100 mmHg.The change of neointimal thickening was analyzed by pathological(HE) study and the proliferation of vascular smooth muscle cells(VSMCs) in neointima was detected by immunohistochemistry (proliferating cell nuclear antigen,PCNA). Results The immunohistochemistry results showed that,on day 7 and 14 after operation,there were more PCNA positive cells in neointima of vein graft in control group than that in  experiment group.The PCNA index in experiment group（23.3±2.8） was lower than that in control group（31.3±4.7）( P<0.05) 7 d after operation. The PCNA index  in experiment group(15.6±0.4) was also lower than that in control group (27.2±5.7)( P<0.01) 14 d after operation.The morphological result showed that the thickness of neointima experiment group(0.50μm±0.02μm) was thinner than that in control group(0.90μm±0.02μm) ( P<0.05). Conclusion The recombinant plasmid Psilencer1.0-U6-siRNA-stat3  can inhibit  the neointimal formation of vein graft obviously.

Key words: recombinatnt plasmid;vein graft;intinal hyperplasia