کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2553966 1124938 2007 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Roles of chymase in stenosis occurring after polytetrafluoroethylene graft implantations
موضوعات مرتبط
علوم پزشکی و سلامت پزشکی و دندانپزشکی کاردیولوژی و پزشکی قلب و عروق
پیش نمایش صفحه اول مقاله
Roles of chymase in stenosis occurring after polytetrafluoroethylene graft implantations
چکیده انگلیسی

Chymase is an important enzyme for the generation of angiotensin (Ang) II and in the activation of transforming growth factor (TGF)-β1. Therefore, chymase may be involved in the hemodialysis access dysfunction, which is caused by intimal hyperplasia that occurs after polytetrafluoroethylene (PTFE) graft implantations. Bilateral U-shaped PTFE grafts were placed between the femoral vein and artery in dogs. Chymase inhibitor (NK3201, 1 mg/kg per day, p.o.) treatments were initiated 3 days before the operation. After the implantation, the stenosis by neointima proliferation was most frequently observed in the venous side of the PTFE grafts. In the hyperplastic neointima, myofibroblasts were the main cellular components. On the other hand, fibroblasts only occupied cellular components in a much smaller proportion in the neointima. However, these cells seem to be rich in the properties of proliferation and migration. After PTFE graft implantations, extensive accumulations of chymase-positive mast cells were found mainly in the tissue surrounding the grafts. The Ang II- and TGF-β-positive cells were found in an adjacent section that was in close proximity to the chymase-positive cells. In contrast, the AT1 receptors, as well as TGF-β type II receptors, were expressed either in the neointima or in the outside adventitia of the PTFE grafts. Chymase inhibitor treatment resulted in a reduction of chymase, Ang II and TGF-β1 expression, leading to a significant inhibition of neointimal formation. These findings indicating that an increase of chymase via promoting Ang II and TGF-β1 generation plays a pivotal role in the neointimal formation after the implantation of PTFE grafts and also suggesting that chymase inhibition may be a new strategy that can be used to prevent PTFE graft dysfunctions in clinical settings.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Life Sciences - Volume 81, Issue 16, 29 September 2007, Pages 1291–1300
نویسندگان
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