METABOLIC AND STRUCTURAL STUDIES OF POLYUNSATURATED LIPIDS IN CELL MEMBRANES

这项研究的主要目的是阐明结构和 多不饱和脂肪酸和磷脂的代谢功能 特别提到乙醇对它们的调节作用。以下几种方法可用于 这个问题被提出了，包括对细胞脂质成分的研究， 膜不对称、脂肪酸氧合和饮食补充。在……里面 具体地说，这些研究集中在大脑的主要多不饱和区， 二十二碳六烯酸(C22：6w3)，对花生四烯酸较少 C20：4w6)。 共价标记技术的发展取得了进展 这使得研究氨基磷脂分子种类组成成为可能。 和膜拓扑结构。已取得以下资料以供参考： 人类红细胞中有50多种。一般说来， 分子物种的不对称性已得到证实，即多不饱和化合物 选择性地定位在质膜的细胞质小叶上。 饮食中补充w-3脂肪酸导致替代 主要是烯基-20：4W6磷脂酰乙醇胺(PE)与 相应20：5W3或22：6W3，减少18：2W6和20：4W6产品 相对于w-6补充组。尿液中的PGI3代谢物也 增加，但没有证据表明PGI2代谢减少。 羟基二十二碳六烯酸酯(HDHE)已被生物合成用于 药理实验中观察到它们有微弱的 对血管的收缩作用，也能拮抗血栓素- 诱导性收缩。血小板HDHEs是立体选择性形成的，但 脑产物似乎是外消旋混合物。

The principal objective of this study is to elucidate the structural and metabolic functions of polyunsaturated fatty acids and phospholipids with particular reference to their modulation by ethanol. Several approaches to this problem were taken, including studies of cellular lipid composition, membrane asymmetry, fatty acid oxygenation and dietary supplementation. In particular, these studies focused on the major polyunsaturate of brain, docosaheaenoate (C22:6w3) and, to a lesser extent, on arachidonate (C20:4w6). Progress has been made in the development of a covalent labelling technique that allows the study of aminophospholipid molecular species composition and membrane topology. Data for reference purposes has been obtained for more than 50 species in the human erythrocyte. Generally, the phenomenon of molecular species asymmetry has been confirmed, i.e. polyunsaturates are selectively localized on the cytoplasmic leaflet of the plasma membrane. Dietary supplementtation with w-3 fatty acids leads to replacement primarily of alkenyl-20:4w6 phosphatidylethanolamines (PE) with the corresponding 20:5w3 or 22:6w3 and decreased 18:2w6 and 20:4w6 products relative to an w-6 supplemented group. Urinary PGI3 metabolites are also increased but there was no evidence of a decrease in PGI2 metabolism. Hydroxy-docosahexaenoates (HDHE) have been biosynthesized for pharmacological experiments in which it was observed that they have a weak contractile action on smooth muscle and can also antagonize thromboxane- induced contractility. Platelet HDHEs were steroselectively formed but the brain p0roducts appear to be racemic mixtures.