Proulx P, McNeil J, Brglez I, Williamson D G
Can J Biochem. 1982 Sep;60(9):904-9. doi: 10.1139/o82-116.
Conditions for uptake of lipids by rabbit intestinal brush border membrane preparations were investigated. A variety of lipids were found to be incorporated, including choline and ethanolamine phosphatides as well as cholesterol, diglyceride, and fatty acid. The incorporation of those lipids tested was enhanced by Ca2+ and other divalent cations but not by monovalent cations. The optimal Ca2+ concentration was approximately 10 mM. The uptake varied with lipid and membrane protein concentration and proceeded at rates which were too rapid to measure under several assay conditions tried. Incorporations were decreased substantially outside the pH range of 6.5-8.0. The effect of one lipid, phosphatidylcholine, on the structural appearance of the membrane fraction was examined by electron microscopy. No free or surface-bound lipid structures could be detected and the membrane fractions appeared to be unchanged after uptake.
研究了兔肠刷状缘膜制剂摄取脂质的条件。发现多种脂质可被摄取，包括胆碱和乙醇胺磷脂以及胆固醇、甘油二酯和脂肪酸。所测试的这些脂质的摄取可被Ca2+和其他二价阳离子增强，但不能被一价阳离子增强。最佳Ca2+浓度约为10 mM。摄取量随脂质和膜蛋白浓度而变化，在几种尝试的测定条件下，摄取速度太快以至于无法测量。在pH值6.5 - 8.0范围之外，摄取量显著降低。通过电子显微镜检查了一种脂质，即磷脂酰胆碱，对膜组分结构外观的影响。未检测到游离或表面结合的脂质结构，摄取后膜组分似乎未发生变化。
