Lange Y, D'Alessandro J S
Biochemistry. 1977 Oct 4;16(20):4339-43. doi: 10.1021/bi00639a002.
The removal from human erythrocytes of cholesterol (mass) and of [3H]cholesterol which had been introduced into the erythrocyte by exchange was studied. Removal was accomplished by incubating erythrocytes in plasma, the free cholesterol content of which had been lowered by the action of lecithin:cholesterol acyltransferase. It was shown that the exchange of cholesterol between erythrocytes and plasma and the net movement of cholesterol out of the membrane into plasma are characterized by the same rate constant and are driven by cholesterol to phospholipid ratios in cells and plasma. The apparent limitation on cholesterol depletion of erythrocytes observed in experiments of this type is explicable as the result of equilibrium between cholesterol in the membrane and in the plasma, an equilibrium reached when there is still cholesterol left in the cells. It is concluded from this study that all the exchangeable cholesterol in human erythrocytes is available for removal from the membrane.
研究了从人红细胞中去除胆固醇（质量）以及通过交换引入红细胞的[3H]胆固醇的情况。通过将红细胞在血浆中孵育来实现去除，血浆中的游离胆固醇含量因卵磷脂：胆固醇酰基转移酶的作用而降低。结果表明，红细胞与血浆之间胆固醇的交换以及胆固醇从膜向血浆的净移动具有相同的速率常数，并且受细胞和血浆中胆固醇与磷脂比例的驱动。在这类实验中观察到的红细胞胆固醇耗竭的明显限制可以解释为膜中胆固醇与血浆中胆固醇达到平衡的结果，当细胞中仍有胆固醇时就达到了这种平衡。从这项研究得出的结论是，人红细胞中所有可交换的胆固醇都可从膜中去除。
