Hariri R J, Hajjar D P, Coletti D, Alonso D R, Weksler M E, Rabellino E
Department of Pathology, Cornell University Medical College, New York, NY 10021.
Am J Pathol. 1988 Apr;131(1):132-6.
Intimal cell proliferation is a "hallmark" of atherosclerosis. Myointimal hyperplasia in arteries has been shown to be dependent on age after vascular endothelial denudation and injury associated with vascular transplantation. Because myointimal thickening is greater in aged rats than in younger rats, and aortic segments from old rats transplanted into young syngeneic recipients have a greater myointimal proliferative response to injury than its host environment, the authors examined the cell cycle distributions of old and young rat arterial smooth muscle cells (SMCs) by flow-cytometric analysis. They observed that there is an apparent age-dependent variation in the cell cycle distribution. Moreover, old SMCs have a greater percentage of their population in the S phase and not G2/M, compared with young SMCs; and there is a decrease in the percentage of old cells in the G0/G1 phase as compared with young SMCs. These differences may reflect the cellular changes observed during myointimal hyperplasia following vascular injury. It is concluded that our data support the hypothesis that the proliferation of SMCs is dependent, in part, on those processes related to aging as well as to the phenotypic state of the cell.
内膜细胞增殖是动脉粥样硬化的一个“标志”。动脉肌内膜增生已被证明在血管内皮剥脱和与血管移植相关的损伤后取决于年龄。由于老年大鼠的肌内膜增厚比年轻大鼠更明显，并且将老年大鼠的主动脉段移植到年轻的同基因受体中，其对损伤的肌内膜增殖反应比宿主环境更大，因此作者通过流式细胞术分析研究了老年和年轻大鼠动脉平滑肌细胞（SMC）的细胞周期分布。他们观察到细胞周期分布存在明显的年龄依赖性变化。此外，与年轻SMC相比，老年SMC处于S期而非G2/M期的细胞比例更高；与年轻SMC相比，老年细胞在G0/G1期的比例有所下降。这些差异可能反映了血管损伤后肌内膜增生过程中观察到的细胞变化。得出的结论是，我们的数据支持这样的假设，即SMC的增殖部分取决于与衰老以及细胞表型状态相关的那些过程。
