Peterson B B, Dacey D M
Department of Biological Structure, The University of Washington, Seattle 98195-7420, USA.
Vis Neurosci. 2000 Jul-Aug;17(4):567-78. doi: 10.1017/s0952523800174073.
To study the detailed morphology of human retinal ganglion cells, we used intracellular injection of horseradish peroxidase and Neurobiotin to label over 1,000 cells in an in vitro, wholemount preparation of the human retina. This study reports on the morphology of 119 wide-field bistratified and 42 diffuse ganglion cells. Cells were analyzed quantitatively on the basis of dendritic-field size, soma size, and the extent of dendritic branching. Bistratified cells were similar in dendritic-field diameter (mean +/- S.D. = 682 +/- 130 microm) and soma diameter (mean +/- S.D. = 18 +/- 3.3 microm) but showed a broad distribution in the extent of dendritic branching (mean +/- S.D. branch point number = 67 +/- 32; range = 15-167). Differences in the extent of branching and in dendritic morphology and the pattern of branching suggest that the human retina may contain at least three types of wide-field bistratified cells. Diffuse ganglion cells comprised a largely homogeneous group whose dendrites ramified throughout the inner plexiform layer. The diffuse cells had similar dendritic-field diameters (mean +/- S.D. = 486 +/- 113 microm), soma diameters (mean +/- S.D. = 16 +/- 2.3 microm), and branch points numbers (mean +/- s.D. = 92 +/- 32). The majority had densely branched dendritic trees and thin, very spiny dendrites with many short, fine, twig-like thorny processes. Five of the diffuse cells had much more sparsely branched dendritic trees (<50 branch points) and less spiny dendrites, suggesting that there are possibly two types of diffuse ganglion cells in human retina. Although the presence of a diversity of large bistratified and diffuse ganglion cells has been observed in a variety of mammalian retinas, little is known about the number of cell types, their physiological properties, or their central projections. Some of the human wide-field bistratified cells in the present study, however, show morphological similarities to monkey large bistratified cells that are known to project to the superior colliculus.
为了研究人类视网膜神经节细胞的详细形态，我们在人视网膜的体外整装标本中，通过细胞内注射辣根过氧化物酶和神经生物素标记了1000多个细胞。本研究报告了119个宽视野双分层和42个弥散型神经节细胞的形态。基于树突野大小、胞体大小和树突分支程度对细胞进行了定量分析。双分层细胞的树突野直径（平均值±标准差=682±130微米）和胞体直径（平均值±标准差=18±3.3微米）相似，但在树突分支程度上呈现出广泛分布（平均值±标准差分支点数=67±32；范围=15 - 167）。分支程度、树突形态和分支模式的差异表明，人类视网膜可能包含至少三种类型的宽视野双分层细胞。弥散型神经节细胞在很大程度上构成一个同质群体，其树突在整个内网层中分支。弥散型细胞具有相似的树突野直径（平均值±标准差=486±113微米）、胞体直径（平均值±标准差=16±2.3微米）和分支点数（平均值±标准差=92±32）。大多数细胞具有密集分支的树突树和细的、非常多棘的树突，带有许多短的、细的、树枝状的棘状突起。其中五个弥散型细胞的树突树分支稀疏得多（<50个分支点）且树突棘较少，这表明人类视网膜中可能存在两种类型的弥散型神经节细胞。尽管在多种哺乳动物视网膜中已观察到存在多种大型双分层和弥散型神经节细胞，但对于细胞类型的数量、它们的生理特性或它们的中枢投射了解甚少。然而，本研究中的一些人类宽视野双分层细胞在形态上与已知投射至上丘的猴大型双分层细胞相似。
