Barter P J, Hopkins G J, Rajaram O V
Baillieres Clin Endocrinol Metab. 1987 Aug;1(3):623-38. doi: 10.1016/s0950-351x(87)80026-5.
Regulation of plasma cholesterol transport is to a large extent a function of factors that regulate plasma cholesterol esterification and the transfers of cholesteryl esters between plasma lipoprotein fractions. Plasma cholesterol esterification is catalysed by the action of lecithin: cholesterol acyltransferase on lipids on the surface of HDL, while the transfers of cholesteryl esters require activity of a specific lipid transfer protein. Esterification of the cholesterol on the surface of HDL generates a concentration gradient down which unesterified cholesterol moves from tissues into the plasma. Once within the plasma and esterified, the newly formed cholesteryl esters are incorporated initially into the core of HDL particles before being redistributed to other classes of lipoproteins. The end result of these processes of esterification and transfer is that most of the cholesterol in human plasma is accommodated within the core of LDL, where its transport is a function of the highly regulated uptake by tissues of intact LDL particles. The capacity of HDL to act as substrates for lecithin: cholesterol acyltransferase varies inversely with HDL particle size. Thus, factors such as the concentration of triglyceride-rich lipoproteins and activities of the lipid transfer protein, hepatic lipase, lipoprotein lipase and the HDL conversion protein, which are known to influence HDL particle size, may also be important as regulators of plasma cholesterol esterification.
血浆胆固醇转运的调节在很大程度上取决于调节血浆胆固醇酯化以及胆固醇酯在血浆脂蛋白组分之间转移的因素。血浆胆固醇酯化是由卵磷脂胆固醇酰基转移酶作用于高密度脂蛋白（HDL）表面的脂质来催化的，而胆固醇酯的转移则需要特定脂质转运蛋白的活性。HDL表面胆固醇的酯化产生了一个浓度梯度，未酯化的胆固醇顺着这个梯度从组织进入血浆。一旦进入血浆并被酯化，新形成的胆固醇酯最初会被整合到HDL颗粒的核心，然后再重新分布到其他类别的脂蛋白中。这些酯化和转移过程的最终结果是，人类血浆中的大部分胆固醇都存在于低密度脂蛋白（LDL）的核心中，其转运取决于组织对完整LDL颗粒的高度调节摄取。HDL作为卵磷脂胆固醇酰基转移酶底物的能力与HDL颗粒大小成反比。因此，已知会影响HDL颗粒大小的因素，如富含甘油三酯的脂蛋白浓度以及脂质转运蛋白、肝脂酶、脂蛋白脂酶和HDL转化蛋白的活性，也可能作为血浆胆固醇酯化的调节因子而发挥重要作用。
