FLUORESCENCE STUDIES OF BIOPHYSICAL PROPERTIES OF POLYUNSATURATED PHOSPHOLIPIDS

多不饱和磷脂生物物理性质的荧光研究

• 批准号: 5200231
• 负责人: B LITMAN
• 金额: --
• 依托单位: NATIONAL INSTITUTE ON ALCOHOL ABUSE AND ALCOHOLISM
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/5200231
• 关键词: biophysics; drug interactions; drug tolerance; ethanol; fatty acylation; fluorescent dye /probe; lipid bilayer membrane; long chain fatty acid; membrane activity; membrane lipids; membrane structure; phase change; phospholipids; unsaturated fatty acids

Chronic alcohol exposure is known to cause resistance to ethanol-induced membrane disordering measured in vitro, usually referred to as membrane tolerance. Initial studies on the phospholipid acyl chain dependence of the effects of alcohol demonstrate that polyunsaturated acyl chains potentiate the effect of alcohol. This finding, coupled with the observation made in this Laboratory that alcohol depletes the long-chain polyunsaturated fatty acids, such as 20:4n6 and 22:6n3, may provide an explanation for the development of the tolerance effect. A novel model for phospholipid acyl chain packing, developed in this Laboratory, includes the formation of lateral domains, which is driven by the strong interactions of the saturated sn-1 chains relative to the polyunaturated sn-2 chains. This model is supported by our findings that mixtures of disaturated PCs and a dipolyunsaturated (di22:6n3) PC show lateral phase separation in the gel phase. Phase transition studies of a variety of mixed-chain phosphatidylethanolamines (PE) demonstrate that this class of phospholipids can undergo a liquid crystalline to hexagonal II phase transition in the physiological temperature range and may in this way provide unique structural features to the membranes in which they reside.

已知慢性酒精暴露会导致对乙醇诱导的 在体外测量的膜紊乱，通常称为膜 宽容 磷脂酰链依赖性的初步研究 醇的作用表明多不饱和酰基链 增强酒精的作用。 这一发现，加上 该实验室观察到酒精会消耗长链 多不饱和脂肪酸，如20：4 n6和22：6 n3，可以提供 解释耐受性效应的发展。 本文提出了一种新的磷脂酰链堆积模型， 实验室，包括横向域的形成，这是驱动 通过饱和sn-1链相对于 多不饱和的sn-2链。 我们的研究结果支持了这一模型 二饱和PC和二多不饱和（di 22：6 n3）PC的混合物 显示凝胶相中的横向相分离。 相变研究 各种混合链磷脂酰乙醇胺（PE）的证明 这类磷脂可以经历液晶， 在生理温度范围内的六方II相变， 可以以这种方式为膜提供独特的结构特征， 他们居住的地方。