Abstract:Aim To investigate the effect of high wall shear stress (WSS) caused by arterio-venous fistula (AVF) on neointimal hyperplasia (NIH) after stent implantation. Methods 36 male New Zealand white rabbits were randomly divided into three groups with 12 rabbits in each group:stent group:right common carotid artery (CCA) stent implantation; stent+arterio-venous fistula (AVF) group:right CCA stent implantation and right carotid AVF; control group:no treatment. After 21 days, CCA specimen of stent segment was taken for histological staining and protein expression analysis. Results In stent segment CCA, WSS was maintained at 43.2%-48.9% of baseline in stent group, and WSS gradually increased to 86% above baseline level in stent+AVF group. NIH in stent+AVF group was less than that in stent group (neointimal area:0.19 mm2 vs. 0.87 mm2; neointima-to-media area ratio:0.18 vs. 1.13). Western blot results showed that the level of endothelial nitric oxide synthase (eNOS) in the stent+AVF group was significantly higher than that in the stent group, while the levels of proliferating cell nuclear antigen (PCNA), vascular cell adhesion molecule-1 (VCAM-1), phosphorylated p38 mitogen-activated protein kinase (p-p38) and phosphorylated c-Jun NH2-terminal protein kinase (p-JNK) in the stent+AVF group were significantly lower than those in the stent group. Conclusion High WSS induced by AVF can reduce NIH after stent implantation, and its potential mechanism may be related to the regulation of eNOS, VCAM-1, p38 and JNK expression and activation.