人腹主动脉分支部内膜增龄性变化的超微结构

为探讨年龄与动脉粥样硬化发生发展的关系 ,选取出生 1日至 77岁之间各年龄段尸体解剖例的腹主动脉与肠系膜下动脉之分支部 30例 ,用透射电镜观察其血流分流处尖端与分支部近心端侧壁内膜的增龄性变化。结果发现 ,随着年龄增加 ,血流分流处尖端的内膜厚度无明显变化 ,平滑肌细胞由合成型变为收缩型 ,且数量减少 ,无一例动脉粥样硬化病变 ;而分支部近心端侧壁内膜随年龄增大而增厚 ,平滑肌细胞多保持合成状态 ,数量略增 ,出现脂质沉积、水肿等不同程度的动脉粥样硬化。提示分支部近心端侧壁内膜的增龄性变化是其易发生动脉粥样硬化病变的形态学基础 ,很可能与此处的血流动力学状态有关

Ultrastructure of Aging Changes in Intima at Branch Regions of Abdominal Aorta

Aim To investigate the relationship between age a nd the development o f atherosclerosis. Methods The mictroarchitecture of intima at apical and later al zones was studied respectively at branch regions of human abdominal aorta in f erior mesenteric artery using transmission electron microscopy (n=30, age ranges from 1 day to 77 years). Results With aging, the th ickness of intima had no a pparent changes at apical zones, where smooth muscle cells turned into constract ile phenotypies and decreased in number, without atherosclerotic lesions; While the thickness of intima increased significantly, where smooth muscle cells remai ned in synthetic states and slightly increased in number, with some atherosclero tic lesions such as lipid deposition, edema, et al. Conclusions The intima at lateral zones has some distinct structural peculiarities with age, which is morp hological basis of atherosclerosis. That is likely caused by hemodynamic status there.