Singer M A, Finegold L
Department of Medicine, Queen's University, Kingston, Ontario, Canada.
Biophys J. 1990 Jan;57(1):153-6. doi: 10.1016/S0006-3495(90)82516-9.
The interaction of cholesterol with lipid membranes has been studied by differential scanning calorimetry on liposomes, a technique which involves only the natural lipids, with no exogeneous probes. The influence of cholesterol at different molar percent concentrations c on the enthalpy delta H of the main gel to liquid crystal phase transition of saturated phosphatidylcholines of acyl chain length n = 12-20 was well represented by delta H = -9.43 + 1.01n - 0.268c kcal/mol. The linear dependence of delta H simultaneously upon chain length n and upon cholesterol concentration c shows clearly that cholesterol interacts with the deeper part of the lipids, as well as the superficial parts. This observation is not accommodated in any of the current models of cholesterol-lipid interactions.
通过对脂质体进行差示扫描量热法研究了胆固醇与脂质膜的相互作用,该技术仅涉及天然脂质,不使用外源探针。在酰基链长度n = 12 - 20的饱和磷脂酰胆碱从主要凝胶相向液晶相转变的过程中,不同摩尔百分比浓度c的胆固醇对焓变ΔH的影响可以很好地用ΔH = -9.43 + 1.01n - 0.268c千卡/摩尔来表示。ΔH同时对链长度n和胆固醇浓度c的线性依赖性清楚地表明,胆固醇不仅与脂质的表面部分相互作用,还与脂质的更深部分相互作用。目前任何胆固醇-脂质相互作用模型都无法解释这一观察结果。