Kolb H, Fernandez E, Schouten J, Ahnelt P, Linberg K A, Fisher S K
Ophthalmology Department, John A. Moran Eye Center, Salt Lake City, Utah 84132.
J Comp Neurol. 1994 May 15;343(3):370-86. doi: 10.1002/cne.903430304.
Golgi-impregnated horizontal cells (HCs) as viewed in whole mount human retinas have been studied by light microscopic (LM) techniques. Impregnated HCs have been drawn by camera lucida and by the Eutectics neuron tracing method to provide quantitative data on dendritic tree sizes, dendritic tree shapes, and dendritic terminals for statistical treatment and cluster analysis. In addition, fractal analyses of HC dendritic branching patterns have been performed. Three significantly different HCs can be classified on both subjective and objective morphological criteria in central and peripheral human retina. In the fovea all HCs are so small that it is difficult to achieve a clear separation of the subtypes, although they can be distinguished by the experienced observer. HI types are the classic HCs of Polyak (The Retina, Chicago: University of Chicago Press, 1941) with distinct dendritic terminal clusters going to cones and a fan-shaped axon terminal consisting of large numbers of rod-destined terminals. HII cells have profusely branched, overlapping dendrites, with poorly defined terminals going to cones and a short curled axon bearing small terminals also going to cones. The HIII types exhibit larger diameter, more asymmetrically shaped dendritic trees and 30% more dendritic terminal clusters than HI cells at any location on the retina. Many HIII cells appear to emit a process from the cell body in the inner nuclear layer (INL) that descends into the outer strata of the inner plexiform layer (IPL). The axon of the HIII cell may end in a loosely organized, sprawling arborization. Fractal dimensions of the horizontal cells also show significant differences between the three groups. HII cells exhibit the highest fractal dimension followed by HI and HIII cells with lower and lowest fractal dimensions, respectively. The fractal dimension of HII cells of rhesus monkey, as determined from drawings by other authors in other publications, are the same as HII cells of human retina.
利用光学显微镜（LM）技术，对经高尔基染色的人视网膜整装标本中的水平细胞（HCs）进行了研究。通过明视野绘图和共晶神经元追踪法绘制了染色的水平细胞，以提供有关树突树大小、树突树形状和树突末梢的定量数据，用于统计处理和聚类分析。此外，还对水平细胞树突分支模式进行了分形分析。根据主观和客观形态学标准，可将人视网膜中央和周边的水平细胞分为三种明显不同的类型。在中央凹，所有水平细胞都非常小，尽管经验丰富的观察者可以区分它们，但很难清晰地分离出各亚型。HI型是Polyak（《视网膜》，芝加哥：芝加哥大学出版社，1941年）描述的经典水平细胞，其树突末梢簇明显伸向视锥细胞，轴突末梢呈扇形，由大量伸向视杆细胞的末梢组成。HII细胞有大量分支且相互重叠的树突，伸向视锥细胞的末梢不清晰，短而卷曲的轴突带有也伸向视锥细胞的小末梢。HIII型在视网膜的任何位置都表现出直径更大、形状更不对称的树突树，其树突末梢簇比HI细胞多30%。许多HIII细胞似乎从内核层（INL）的细胞体发出一个突起，向下延伸到内网状层（IPL）的外层。HIII细胞的轴突可能终止于一个松散组织、杂乱的分支结构。三组水平细胞的分形维数也存在显著差异。HII细胞的分形维数最高，其次是HI细胞，HIII细胞的分形维数最低。根据其他作者在其他出版物中的绘图确定，恒河猴HII细胞的分形维数与人视网膜HII细胞相同。
