Reichenbach A, Ziegert M, Schnitzer J, Pritz-Hohmeier S, Schaaf P, Schober W, Schneider H
Carl Ludwig Institute of Physiology, Leipzig University, FRG.
Brain Res Dev Brain Res. 1994 May 13;79(1):72-84. doi: 10.1016/0165-3806(94)90050-7.
A qualitative and quantitative description of the columnar units in the mammalian retina, and a discussion of their ontogeny and putative functions is given. Columnar arrangements of cells exist in the developing retina which can be observed by means of scanning electron microscopy. In the adult retina, each Müller cell ensheaths a columnar group of neuronal cells. Counting the number of cells in radial H/E stained sections at various developmental stages reveals a constant ratio of neuronal cells per Müller cell, independent of the developmental stage (after postnatal day 9), and independent of the retinal topography. Such groups of cells always consist of one Müller cell, 11 rod photoreceptor cells, about 2 bipolar cells, and 1 to 2 amacrine cells. Retinal ganglion cells, cone photoreceptor cells, and horizontal cells are more sparsely distributed in the retina than these units; since they are known to arise earlier in the ontogenesis than other cell types they are considered to exist independently of the columnar units. It is suggested that the units arise by migration of groups of preneurons along a common Müller (precursor) cell; these preneurons and the corresponding Müller cell may be clonally related. In the adult retina, such columns might constitute metabolic and functional units.
本文对哺乳动物视网膜中的柱状单元进行了定性和定量描述，并讨论了它们的个体发育及假定功能。在发育中的视网膜中存在细胞的柱状排列，可通过扫描电子显微镜观察到。在成年视网膜中，每个米勒细胞包裹着一组柱状神经细胞。通过对不同发育阶段的放射状苏木精-伊红染色切片中的细胞进行计数发现，每个米勒细胞所含神经细胞的比例恒定，与发育阶段（出生后第9天之后）无关，也与视网膜的局部解剖位置无关。这样的细胞组通常由一个米勒细胞、11个视杆光感受器细胞、约2个双极细胞以及1至2个无长突细胞组成。视网膜神经节细胞、视锥光感受器细胞和水平细胞在视网膜中的分布比这些单元更为稀疏；由于已知它们在个体发育过程中比其他细胞类型更早出现，因此被认为独立于柱状单元而存在。有人提出，这些单元是由神经前体细胞群沿着共同的米勒（前体）细胞迁移形成的；这些神经前体细胞和相应的米勒细胞可能存在克隆关系。在成年视网膜中，这样的柱状结构可能构成代谢和功能单元。
