Anders J J, Brightman M W
J Neurocytol. 1979 Dec;8(6):777-95. doi: 10.1007/BF01206676.
Orthogonal arrays of small intramembranous particles characterize freeze-fractured astrocytic plasma membranes. The normal variation of assemblies in plasma membranes of subpial astrocytic processes in mature and developing rats was established and compared with assemblies in plasma membranes of reactive astrocytes. In mature rats, subpial astrocytic processes had the greatest number of assemblies. As the parenchyma was approached, this number decreased in each successive layer of astrocytic processes. The advent of assemblies within the plasma membrane is a new criterion of astrocytic differentiation. The foot processes of subpial astrocytes in foetal rats began to acquire assemblies between day 19 and 20 and continued to mature postnatally by a constant addition and rearrangement of assemblies. In contrast to the paucity of assemblies in deeper laminae of the normal brain, reactive astrocytes comprising the lower lamellae in glial scars had an increased number of assemblies while the most striking feature of the superficial, astrocytic processes within the scar was a rearrangement of assemblies. Although the function of these intramembranous particles in still unknown, it appears from our measurements that they are localized primarily in the outermost astrocytic foot process and to a progressively lesser degree in the underlying astrocytic lamellae.
小膜内颗粒的正交排列是冷冻断裂的星形胶质细胞质膜的特征。确定并比较了成熟和发育中大鼠软膜下星形胶质细胞突起质膜中组装体的正常变化，并与反应性星形胶质细胞质膜中的组装体进行了比较。在成熟大鼠中，软膜下星形胶质细胞突起的组装体数量最多。随着接近实质，在星形胶质细胞突起的每一层中，这个数量都会减少。质膜内组装体的出现是星形胶质细胞分化的一个新标准。胎鼠软膜下星形胶质细胞的足突在第19天到20天之间开始获得组装体，并在出生后通过不断添加和重新排列组装体而持续成熟。与正常脑深部层中组装体的稀少形成对比的是，构成胶质瘢痕下层的反应性星形胶质细胞的组装体数量增加，而瘢痕内表面星形胶质细胞突起最显著的特征是组装体的重新排列。尽管这些膜内颗粒的功能仍然未知，但从我们的测量结果来看，它们主要定位于最外层的星形胶质细胞足突，而在下面的星形胶质细胞层中的定位程度逐渐降低。
