Sabesin S M, Holt P R
Lipids. 1975 Dec;10(12):840-6. doi: 10.1007/BF02532330.
Intracellular triglyceride accumulation and delayed chylomicron secretion were demonstrated in distal but not in proximal rat intestine following prolonged steady state fat absorption. After 1 and 4 hr of intraduodenal triolein infusion, the mucosal triglyceride content in distal intestinal segments was greatly increased compared with proximal segments. Electron microscopy at each time interval disclosed greater quantities of lipid droplets within the distal cells and these were much larger than the intracellular droplets in the proximal cells, some attaining an enormous size (9000 mum). When proximal and distal cells were compared at intervals after cessation of a 4 hr triolein infusion, the differences in intracellular lipid accumulation were also evident because, even after 6 hr the distal cells were still filled with large droplets, whereas the proximal cells were almost devoid of fat. These results indicate a basic cellular difference between proximal and distal intestine in the processing of fat and, in contrast to current concepts, suggest that defective chylomicron secretion is not necessarily associated with limited B-apoprotein availability.
在长时间稳态脂肪吸收后，大鼠远端而非近端肠道出现细胞内甘油三酯蓄积和乳糜微粒分泌延迟。十二指肠内注入甘油三酯1小时和4小时后，远端肠段的黏膜甘油三酯含量与近端肠段相比大幅增加。在每个时间间隔进行的电子显微镜检查显示，远端细胞内的脂滴数量更多，且这些脂滴比近端细胞内的脂滴大得多，有些脂滴达到了巨大的尺寸（9000微米）。在4小时甘油三酯注入停止后的不同时间间隔比较近端和远端细胞时，细胞内脂质蓄积的差异也很明显，因为即使在6小时后，远端细胞仍充满大脂滴，而近端细胞几乎没有脂肪。这些结果表明近端和远端肠道在脂肪处理过程中存在基本的细胞差异，并且与当前观点相反，提示乳糜微粒分泌缺陷不一定与β-载脂蛋白可用性受限有关。
