Fleenor Bradley S, Bowles Douglas K
Department of Biomedical Sciences, University of Missouri, Columbia, MO 65211, USA.
Am J Physiol Heart Circ Physiol. 2009 May;296(5):H1532-9. doi: 10.1152/ajpheart.00566.2008. Epub 2009 Feb 27.
Adventitial fibroblasts have previously been proposed to be a major constituent of the neointima following coronary balloon angioplasty. The present study utilized the bromodeoxyuridine (BrdU) pulse-chase technique to track adventitial fibroblast migration early after balloon injury in swine. BrdU (30 mg/kg), a marker of proliferating cells, was given intravenously 1 or 2 days after balloon angioplasty. For each time point, one animal was euthanized 24 h after injection to identify the location of the proliferating cells, while a second animal was euthanized 25 days after angioplasty to determine whether the proliferating cells migrated to form the neointima. Our results demonstrate that BrdU-positive cells were located primarily in the adventitia with all three time points 24 h after balloon angioplasty. Furthermore, when BrdU was injected on day 1 or 2 only 0.65 +/- 0.17% and 1.7 +/- 0.64%, respectively, of neointimal cells were BrdU positive on day 25. In conclusion, these results demonstrate a negligible contribution of coronary adventitial fibroblasts to neointima formation following coronary balloon angioplasty, supporting the concept that the neointima is primarily of smooth muscle cell origin.
以往有观点认为，冠状动脉球囊血管成形术后，外膜成纤维细胞是新生内膜的主要组成部分。本研究采用溴脱氧尿苷（BrdU）脉冲追踪技术，在猪球囊损伤后早期追踪外膜成纤维细胞的迁移情况。在球囊血管成形术后1天或2天静脉注射BrdU（30mg/kg），BrdU是增殖细胞的标志物。对于每个时间点，在注射后24小时处死一只动物，以确定增殖细胞的位置，同时在血管成形术后25天处死另一只动物，以确定增殖细胞是否迁移形成新生内膜。我们的结果表明，在球囊血管成形术后24小时的所有三个时间点，BrdU阳性细胞主要位于外膜。此外，当在第1天或第2天注射BrdU时，在第25天新生内膜细胞中BrdU阳性的分别仅为0.65±0.17%和1.7±0.64%。总之，这些结果表明冠状动脉外膜成纤维细胞对冠状动脉球囊血管成形术后新生内膜形成的贡献可忽略不计，支持新生内膜主要起源于平滑肌细胞的观点。
