Lane B P
J Cell Biol. 1965 Oct;27(1):199-213. doi: 10.1083/jcb.27.1.199.
The fine structure of the longitudinal layer of the tunica muscularis of the mouse jejunum was studied in various stages of mechanically stimulated contraction. The relaxed cell is long and narrow with smooth cytoplasmic and nuclear contours. As contraction progresses, the cell becomes ellipsoid and its borders exhibit invaginations at the points of myofilamentous attachment to the plasma membrane and vesicle-containing projections of the intervening membrane. These changes are interpreted as representing the deforming forces applied by the myofilaments to the plasma membrane. The nucleus of the contracted cell is shortened and widened, with convolution of its limiting membranes. This alteration, as well as progressive changes in the alignment of cytoplasmic organelles, is thought to be due to forces exerted on the internal structure of the cell by the contractile elements. The myofilaments form a network of oriented bundles during contraction. Aggregates of filaments of two different diameters are noted. The two sizes of filaments intermingle only in small areas of increased density. These dense areas increase in length and number during contraction. A model of the functional organization of the cell is proposed.
对处于机械刺激收缩不同阶段的小鼠空肠肌层纵行层的精细结构进行了研究。松弛状态下的细胞又长又窄，细胞质和细胞核轮廓光滑。随着收缩的进行，细胞变成椭圆形，其边界在肌丝附着于质膜的点以及中间膜含囊泡的突起处出现内陷。这些变化被解释为代表肌丝施加于质膜的变形力。收缩细胞的细胞核缩短变宽，其界限膜出现卷曲。这种改变以及细胞质细胞器排列的渐进变化被认为是由于收缩元件对细胞内部结构施加的力所致。肌丝在收缩过程中形成定向束的网络。注意到有两种不同直径的细丝聚集体。两种大小的细丝仅在密度增加的小区域相互交织。这些密集区域在收缩过程中长度和数量增加。提出了细胞功能组织的模型。
