EFFECTS OF PUROMYCIN ON THE STRUCTURE OF RAT INTESTINAL EPITHELIAL CELLS DURING FAT ABSORPTION
EFFECTS OF PUROMYCIN ON THE STRUCTURE OF RAT INTESTINAL EPITHELIAL CELLS DURING FAT ABSORPTION
复制标题
嘌呤霉素对脂肪吸收过程中大鼠肠上皮细胞结构的影响
作者：
H. Friedman;R. Cardell
本报告提供了有关大鼠肠上皮细胞在脂肪吸收过程中的形态学信息。此外，蛋白质代谢在这一过程中的作用已被评估，通过阻断其合成与嘌呤霉素和研究的精细结构的粘膜细胞从大鼠在脂肪插管后的不同时间。结果表明，SER衍生的小泡，含有脂肪滴，迁移从顶端细胞质的吸收细胞和融合囊泡或高尔基复合体的液泡。论证了高尔基复合体在完成乳糜微粒形成和为乳糜微粒提供适当的包膜方面是重要的。这种膜可能是高尔基体液泡与侧细胞膜融合并释放乳糜微粒所必需的。嘌呤霉素处理导致吸收细胞积累增加的脂质量，这些脂质在脂肪吸收过程中缺乏膜。此外，嘌呤霉素处理的细胞含有更少的粗面内质网和高尔基体膜的数量显着减少。在本文中，我们讨论了这些异常的后果，并建议继续蛋白质合成的粗面内质网是必需的，以产生高尔基体膜。如果没有这种膜，细胞清除乳糜微粒的能力就会受损，脂质就会积聚。
This report provides information on the morphology of rat intestinal epithelial cells during fat absorption. In addition, the role of protein metabolism in this process has been evaluated by blocking its synthesis with puromycin and studying the fine structure of mucosal cells from rats at various times after fat intubation. The results indicate that SER-derived vesicles, containing fat droplets, migrate from the apical cytoplasm of the absorptive cell and fuse with saccules or vacuoles of the Golgi complex. Arguments are made that the Golgi complex is important in completing chylomicron formation and in providing appropriate enveloping membranes for the chylomicron. Such membranes may be necessary for Golgi vacuoles to fuse with the lateral cell membranes and release chylomicra. Puromycin treatment causes the absorptive cell to accumulate increased quantities of lipid that are devoid of membrane during fat absorption. In addition, puromycin-treated cells contain much less RER and Golgi membranes are strikingly decreased in number. In this paper we discuss the consequences of these abnormalities and suggest that continued protein synthesis by the RER is required in order to generate Golgi membranes. If such membranes are absent the cell's ability to discarge chylomicra is impaired and lipid accumulates.