Pu M
Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, Utah 84132, USA.
J Comp Neurol. 1999 Nov 15;414(2):267-74.
The morphological properties of cat retinal ganglion cells projecting to the suprachiasmatic nucleus (SCN) of the hypothalamus were studied by using retrograde labeling, in vitro intracellular injection, confocal optical section, and computer three-dimensional reconstruction techniques. A total of 218 stained cells were studied. Neither the dendritic fields nor soma diameters of SCN-projecting cells varied with eccentricity. Approximately 50% of cells were concentrated not in the area centralis, but rather in the visual streak. SCN-projecting cells showed large and symmetrical dendritic fields (596 +/- 159 microm) and medium to small sized somas (17.2 +/- 3.3 microm). The ramification patterns of SCN-projecting cells were similar. Most cells primarily ramify in either sublamina A or B. Evidence from quantitatively analyzed cells (n = 39) suggests that these cells ramified more frequently in sublamina A (n = 17) than in sublamina B (n = 8). A large number of cells, on the other hand, showed diffuse ramification (n = 14) throughout the inner plexiform layer (IPL). The functional roles of these cells and the corresponding retinal neurocircuitry in circadian entrainment remain to be studied.
利用逆行标记、体外细胞内注射、共聚焦光学切片和计算机三维重建技术，研究了投射到下丘脑视交叉上核（SCN）的猫视网膜神经节细胞的形态学特性。共研究了218个染色细胞。投射到SCN的细胞的树突野和胞体直径均不随偏心率而变化。约50%的细胞并非集中在中央区，而是集中在视条纹。投射到SCN的细胞显示出大而对称的树突野（596±159微米）和中小尺寸的胞体（17.2±3.3微米）。投射到SCN的细胞的分支模式相似。大多数细胞主要在A层或B层分支。对定量分析的细胞（n = 39）的研究表明，这些细胞在A层（n = 17）的分支比在B层（n = 8）更频繁。另一方面，大量细胞在整个内网状层（IPL）显示出弥散分支（n = 14）。这些细胞以及相应的视网膜神经回路在昼夜节律调节中的功能作用仍有待研究。
