Valsartan eluting-stents inhibited neointimal hyperplasia by decreasing collagen deposition in rabbits
Wang, L.; Jia, S-qing.; Li, G-hua.; Chen, H.; Li, H-wei.; Zhao, L.; Yao, D-kuo.; Ding, R-jing.
Zhonghua Xin Xue Guan Bing Za Zhi 34(5): 450-453
2006
ISSN/ISBN: 0253-3758 PMID: 16776965 Document Number: 600463
Objective To assess the effect of valsartan eluting-stents on restenosis and collagen deposition in neointima hyperplasia in rabbits. Methods Valsartan eluting-stents and the carrier eluting-stents were made with patented multi-layers coating techniques. Bare stents (n = 8), carrier eluting-stents ( n = 8) and valsartan eluting-stents ( n = 10) were implanted into rabbit abdominal aortas, respectively. Quantitive angiography (QA) was performed before, immediately post and 3 months after stents implantations to determine the diameter of aortas. Rabbits were killed 3 months post stents implantation and the cross sections of the stented vessels were analyzed for neointimal formation: luminal area ( LA), neointimal area (NIA), inner elastic lumina area (IELA), the maximal inner-membrane thickness (MIT) and percent stenosis. MASSON and picrosirius red staining were performed to observe the collagen deposition in neointima analyzed. Results The mean aortic diameters measured by QA at different time points were similar between the groups. LA was significantly larger (5016 269 mu m(2) +/- 207 934 mu m(2) vs. 4 345 548 mu m(2) 125 822 mu m(2) and 4 302 061 mu m(2) 167 952 mu m(2), p < 0.01 vs. valsartan stents) while NIA (441 577 mu m(2) +/- 74 099 mu m(2) vs. 1 119635 mu m(2) +/- 163 503 mu m(2) and 1 135 636 mu m(2) +/- 136 555 mu m(2)) and MIT (116 mu m +/- 12 mu m vs. 240 mu m +/- 30 mu m and 192 mu m(2) +/- mu m) as well as percent stenosis (8% +/- 2% vs. 20% +/- 2% and 21% +/- 2%) were significantly reduced in valsartan eluting-stents group compared to bare and carrier stents groups. MASSON and picrosirius red staining revealed rich type E collagen deposition in neointima and spare type I collagen patched around stents struts in bare and carrier stents groups and collagen deposition was rarely seen in neointima and stents struts in valsartan eluting-stents group. Conclusion Valsartan eluting-stents inhibited neointimal hyperplasia by decreasing collagen deposition.