具有不同不饱和程度的杂酸磷脂酰胆碱对胆固醇的反应不同。

Heteroacid phosphatidylcholines with different amounts of unsaturation respond differently to cholesterol.

作者信息

Hernandez-Borrell J, Keough K M

机构信息

Department of Biochemistry, Memorial University of Newfoundland, St. John's, Canada.

出版信息

Biochim Biophys Acta. 1993 Dec 12;1153(2):277-82. doi: 10.1016/0005-2736(93)90416-w.

DOI:10.1016/0005-2736(93)90416-w

PMID:8274498

Abstract

The effectiveness of cholesterol in removing the gel to liquid crystal phase transition of dispersions of pure molecular species of phosphatidylcholines (PC) that is detectable by differential scanning calorimetry (DSC) has been explored. The effect of cholesterol on 16:0-18:0 PC, 16:0-18:1 PC, 16:0-18:2 PC, 16:0-20:4 PC and 16:0-22:6 PC has been determined. Cholesterol caused a concentration-dependent removal of the detectable phase transitions in all cases. It required very little cholesterol to remove the phase transition 16:0-18:2 PC (< 17 mol% of cholesterol in PC). It required > or = 35 mol% cholesterol to remove delta H for 16:0-18:0 PC and 16:0-22:6 PC. About 20-25 mol% cholesterol caused disappearance of the transitional endotherm of 16:0-18:1 PC and 16:0-20:4 PC. The findings indicate that the magnitude of the influence of cholesterol on phospholipid is dependent on the degree of unsaturation in the lipid.

摘要

通过差示扫描量热法（DSC）可检测到，已探究了胆固醇对纯磷脂酰胆碱（PC）分子种类分散体从凝胶相转变为液晶相的有效性。已确定了胆固醇对16:0 - 18:0 PC、16:0 - 18:1 PC、16:0 - 18:2 PC、16:0 - 20:4 PC和16:0 - 22:6 PC的影响。在所有情况下，胆固醇都会导致可检测到的相变呈浓度依赖性消失。去除16:0 - 18:2 PC的相变所需胆固醇极少（PC中胆固醇含量<17 mol%）。去除16:0 - 18:0 PC和16:0 - 22:6 PC的ΔH需要≥35 mol%的胆固醇。约20 - 25 mol%的胆固醇会导致16:0 - 18:1 PC和16:0 - 20:4 PC的转变吸热消失。这些发现表明，胆固醇对磷脂的影响程度取决于脂质中的不饱和度。