Aspirin Intervenes Locally To Prevent And Treat Vein Graft Thrombosis And Neointimal Hyperplasia

Objective:To observe the effect of local aspirin apply around rat graft on thrombosis and neointimal hyperplasia; at the same_time, the level changes of plasma NO, ET-1,VWF and hs-CRP are also analyzed.Methods:SD rat jugular vein-carotid artery interposition model was selected with oral, local, and the combination of aspirin treatment respectively. The rats were divided into control, topical, oral and combined treatment groups. Specimens were harvested at different time postoperatively to investigate the severity of thrombus and neointimal hyperplasia, α-SM-actin and CD-34immunohistochemical analysis also studied. At the same time, the level changes of plasma NO, ET-1, VWF and hs-CRP were also measured using oxidation-reduction or ELISA methods.Results:1. The results showed that vascular thrombosis area in control group is greater than that of the combined treatment group (P<0.05)on the seventh day after surgery. Control group has significantly neointimal hyperplasia compared with both local and combined treatment groups (P<0.05)on the fourteenth day after surgery.2. Seven days after surgery, α-SM-actin immunohistochemistry showed that α-SM-actin+cell proliferation and migration is more obvious in control and oral groups, while the changes were less in the local and combined treatment groups.3. CD-34immunohistochemistry showed that intima CD-34+cells integrity was well preserved in local and combined treatment groups compared with the other two groups.4. Post-surgery, ET-1levels in the control group was significantly higher than that of the other groups (P<0.05), while the NO levels decreased (P<0.05).5. Three days after surgery, oral group VWF level was lower than that of control group (P<0.05). Postoperative7d, the combination treatment group VWF level lower than control group (P<0.05); both oral and combination groups VWF reducing compared with topical medication group (P<0.05); postoperative 14d, both topical and oral groups’VWF level were higher than that of control group (P<0.05).6. Postoperative7d, both control group and combination group hs-CRP level were lower than the local medication group (P<0.05). Postoperative14d, both control and oral groups’hs-CRP level were lower than that of the local treatment group(P<0.05), but the later was higher than that of the combination group(P<0.01).Conclusion:Topical or combination application of aspirin may not only play a part in protecting endothelial cell, but also inhabiting vein graft thrombosis and smooth muscle cell proliferation by increasing NO and reducing ET-1.