Leuenberger P M, Novikoff A B
J Cell Biol. 1975 May;65(2):324-34. doi: 10.1083/jcb.65.2.324.
The pigment epithelial cell of the retina actively participates in two aspects of lipid metabolism: (a) the fatty acid esterification of vitamin A and its storage and transport to the photoreceptors, and (b) the phagocytosis and degradation of the lipoprotein membrane disks shed from the photoreceptor cells. Study of the pigment epithelial cells of adult albino and pigmented rodents has revealed the abundance of an organelle, microperoxisomes, not previously known to exist in this cell type. The metabolism, transport, and storage of lipids are major functions of other cell types which possess large numbers of microperoxisomes associated with a highly developed smooth endoplasmic reticulum. Microperoxisomes were encountered, but relatively rarely, in Müller cells and vascular endothelial cells. A tubular system in photoreceptor terminals is reactive in the cytochemical procedure used to visualize microperoxisomes.
(a)维生素A的脂肪酸酯化及其储存和向光感受器的转运,以及(b)光感受器细胞脱落的脂蛋白膜盘的吞噬和降解。对成年白化和有色啮齿动物色素上皮细胞的研究揭示了一种细胞器——微过氧化物酶体的丰富存在,这种细胞器以前在这种细胞类型中并不为人所知。脂质的代谢、运输和储存是其他细胞类型的主要功能,这些细胞类型拥有大量与高度发达的滑面内质网相关的微过氧化物酶体。在米勒细胞和血管内皮细胞中也发现了微过氧化物酶体,但相对较少。光感受器终末的管状系统在用于可视化微过氧化物酶体的细胞化学程序中具有反应性。