Kobayashi N, Sakai T
Department of Anatomy, School of Medicine, Juntendo University, Tokyo, Japan.
Cell Tissue Res. 1994 Dec;278(3):471-82. doi: 10.1007/BF00331365.
Postnatal change in the distribution of actin filaments in endothelial cells was studied in the rat aorta by use of rhodamine-phalloidin staining and confocal laser scanning microscopy. Endothelial cells of the rat aorta possessed two populations of actin filament bundles, namely, peripheral bands at the cell border and stress fibers running longitudinally in the cytoplasm. Aortic endothelial cells of the neonatal rat contained only stress fibers, whereas those of the 10-day-old rat developed both peripheral bands and stress fibers. After 20 days of age, aortic endothelial cells had predominantly peripheral bands with occasional stress fibers around the branch orifices. During postnatal development the length density of stress fibers in aortic endothelial cells decreased, whereas individual stress fibers in endothelial cells were shortened. Electron-microscopic observation revealed that the high intercellular boundaries of aortic endothelial cells at birth decreased in height and developed cytoplasmic interdigitations after 20 days of age. The occurrence of peripheral bands at the cell border is thought to be closely related to formation of cytoplasmic interdigitation which strengthens the mechanical connection between endothelial cells against increasing transmural pressure. Expression of stress fibers in aortic endothelial cells of the neonatal rat is supposed to be affected by longitudinal elongation of the developing aorta, whereas their postnatal decrease is thought to be correlated with the change of fluid shear stress loaded on the aortic endothelium.
利用罗丹明 - 鬼笔环肽染色和共聚焦激光扫描显微镜技术，研究了大鼠主动脉内皮细胞中肌动蛋白丝分布的产后变化。大鼠主动脉内皮细胞拥有两种肌动蛋白丝束群体，即细胞边界处的周边带和在细胞质中纵向延伸的应力纤维。新生大鼠的主动脉内皮细胞仅含有应力纤维，而10日龄大鼠的主动脉内皮细胞则同时发育出周边带和应力纤维。20日龄后，主动脉内皮细胞主要具有周边带，在分支孔口周围偶尔可见应力纤维。在出生后的发育过程中，主动脉内皮细胞中应力纤维的长度密度降低，而内皮细胞中的单个应力纤维缩短。电子显微镜观察显示，出生时主动脉内皮细胞的高细胞间边界高度降低，20日龄后出现细胞质交错。细胞边界处周边带的出现被认为与细胞质交错的形成密切相关，细胞质交错可增强内皮细胞之间的机械连接以抵抗增加的跨壁压力。新生大鼠主动脉内皮细胞中应力纤维的表达被认为受发育中主动脉纵向伸长的影响，而它们出生后的减少被认为与加载在主动脉内皮上的流体剪切应力的变化相关。
