Changes of apoptosis and expression of related apoptosis regulatory factors in neointima after canine coronary angioplasty / 中国介入心脏病学杂志

ABSTRACT

Objective To investigate the changes of apoptosis and expression of related apoptosis regulatory factors in neointima after canine coronary angioplasty Methods Stents were implanted in the left circumflex coronary artery in 15 canines Arteries were harvested at 1, 4, and 12 weeks after stenting Uninjured arteries were used as controls Apoptosis was demonstrated by the terminal uridine nick end labeling (TUNEL) method and transmission electron microscopy Proliferating cells were identified by immunostaining for proliferating cell nuclear antigen (PCNA) Expressions of Bcl xl proteins were detected by immunohistochemical method and Western blot Results Stents implantment induced intimal hyperplasia Apoptosis was not detected in control vessels Apoptotic cells and PCNA positive cells were identified at 1, 4, and 12 weeks with a peak at 1 week Profiles of apoptosis and cell proliferation after stenting were accordant in neointima, but cell proliferation rates were higher than cell apoptosis rates at all time points Expressions of Bcl-xl proteins were detected at 1 week, peaked at 4 weeks, and lasted till 12 weeks after stenting Conclusion Apoptosis may be an important determinant of in stent restenosis Bcl xl appears to play a critical role in regulating cell apoptosis