Lutton C
Laboratoire Physiologie de la Nutrition (Laboratoire associé à l'INRA), Université Paris-Sud, Orsay, France.
Digestion. 1996;57(1):1-10. doi: 10.1159/000201305.
Quantitative data on cholesterol movements in mucosa cell as a function of its localization in the small intestine have been obtained in normocholesterolemic (SW) or genetically hypercholesterolemic (RICO) rats. Bile cholesterol absorption is greater and more proximal than dietary cholesterol absorption, both taking place mainly in the top cells of the duodenum or the proximal jejunum. Esterification of cholesterol also takes place mainly in the villus cells, while cholesterol synthesis is predominantly carried out in the crypt cells of the proximal duodenum and distal ileum. Cholesterol exchanges, which replace half of the cell cholesterol through the cell life, can be estimated at 3-4%.h-1 between plasma and mucosa cells, according to its location, i.e. 12-25 micrograms.h-1 (per mg cell DNA). In comparison, the cholesterol HDL or LDL uptake appears to be very low (0.02-0.06 and 0.2-0.6 microgram.h-1, respectively). Compartmentalization of cholesterol metabolism in the enterocyte can be suggested by different experimental data. The turnover of newly synthesized cholesterol is about 2-fold lower than that of exogenous (dietary) cholesterol.
在正常胆固醇水平（SW）或遗传性高胆固醇血症（RICO）大鼠中，已获得小肠黏膜细胞中胆固醇转运的定量数据，该数据是其在小肠中定位的函数。胆汁胆固醇的吸收比膳食胆固醇的吸收更大且更靠近近端，两者主要发生在十二指肠顶部细胞或近端空肠中。胆固醇酯化也主要发生在绒毛细胞中，而胆固醇合成主要在近端十二指肠和远端回肠的隐窝细胞中进行。根据其位置，胆固醇交换在血浆和黏膜细胞之间估计为3 - 4%·h⁻¹，通过细胞寿命可替换细胞胆固醇的一半，即12 - 25微克·h⁻¹（每毫克细胞DNA）。相比之下，胆固醇HDL或LDL的摄取似乎非常低（分别为0.02 - 0.06和0.2 - 0.6微克·h⁻¹）。不同的实验数据表明了肠细胞中胆固醇代谢的区室化。新合成胆固醇的周转比外源性（膳食）胆固醇的周转低约2倍。
