Rods and Cones
Rods and Cones
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杆和锥
DOI：
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发表时间：
1972
期刊：
影响因子：
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通讯作者：
A. Cohen
中科院分区：
文献类型：
--
作者：
A. Cohen
脊椎动物的感光细胞，视杆细胞和视锥细胞，检测和传递信息，因此可以被分类为神经元细胞。它们的形态和位置表明与室管膜细胞的进化有关，如Krause（1892，1893，1894）所述。室管膜细胞构成脊椎动物中枢神经系统的中空、充满液体的心室系统的衬里细胞。脊椎动物的眼睛，在一个非常真实的意义上，是大脑的外部化部分。在胚胎发育过程中，眼睛是从轴向神经管的中空侧室形成的，并且管的内腔与侧室的内腔是连续的，称为视泡。纤毛室管膜细胞最终排列在这些腔中。在发育的后期，每个生长的视泡的外侧壁对着内侧壁塌陷，从而形成双壁视杯，其产生的视泡指向外侧。这层膜将形成成熟眼睛的玻璃体腔。视杯的两个壁之间的薄空间作为视网膜（由外侧杯壁的细胞形成）和色素上皮（由内侧杯壁的细胞形成）之间的心室空间而持续存在。脑室空间与脑室的主要系统切断，但保留了其许多功能属性。色素上皮细胞保持为一层细胞，只有一个细胞厚，并由丰富的毛细血管丛支持。在中枢神经系统的任何地方，毛细血管丛和薄的室管膜细胞的结合构成了脉络丛。
The photoreceptor cells of vertebrates, the rods and cones, detect and convey information and may thus be classified as neuronal cells. Their form and position suggests an evolution related to that of ependymal cells, as suggested by Krause (1892, 1893, 1894). The ependymal cells constitute the lining cells of the hollow, fluid filled ventricular systems of vertebrate central nervous systems. The vertebrate eye, in a very real sense, is an externalized portion of the brain. During embryonic development the eyes form from hollow side chambers off the axial neural tube, and the lumen of the tube is continuous with that of the side chambers, known as optic vesicles. Ciliated ependymal cells eventually line these lumina. At a later stage of development, the lateral wall of each growing optic vesicle collapses against the medial wall, thus forming a double walled optic cup, whose resultant concavity is directed laterally. This concavity will form the vitreal chamber of the mature eye. The thin space between the two walls of the optic cup persists as a ventricular space between the retina (formed from cells of the lateral cup wall) and the pigment epithelium (formed by cells of the medial cup wall). The ventricular space becomes cut off from the main system of brain ventricles, yet retains many of its functional attributes. The cells of the pigment epithelium remain as a sheet of cells only one cell thick and become backed by a rich capillary plexus. This combination of a capillary plexus backing a thin sheet of ependymal cells constitutes a choroid plexus as seen anywhere in the central nervous system.