METABOLIC AND STRUCTURAL STUDIES OF POLYUNSATURATED LIPIDS IN CELL MEMBRANES

主要目的是阐明结构和代谢 多不饱和脂肪酸或磷脂的功能， 参考其通过乙醇的调节。 对此有几种方法 采取的问题包括细胞脂质组成的研究， 膜不对称、脂肪酸氧化和膳食补充。 在 特别是，这些研究集中在大脑的主要多功能性， 二十二碳六烯酸（C22：6 w3），在较小程度上，花生四烯酸 (C20：4w6）。 我们现在报告红细胞膜结构的一个新方面，即， 磷脂酰乙醇胺分子种类不对称。 多烯 含有花生四烯酸的物种优先定位于 红细胞膜的细胞质小叶。 然而， 物种在细胞表面的代表性更高。 因为酒精 导致多不饱和磷脂种类的减少，我们假设 膜内部磷脂的选择性损失。 相反，饮食 补充omega-3脂肪酸导致磷脂含量增加， 含有这些酸的物种被定位到膜内部。 热喷雾液相色谱/质谱联用技术的继续发展 用于磷脂物质的光谱（LC/MS）技术已经使得 快速，详细和有效的分析所有主要的脂质 班 在量化方面取得了进展， 使用氘代内标测定磷脂酰胆碱。 酶促氧化22：6 W3的生化特性 继续对大鼠脑匀浆进行pH、酶抑制剂 和各种辅助因子。

The principal objective is to elucidate the structural and metabolic functions of polyunsaturated fatty acids or 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, docosahexaenoate (C22:6w3) and, to a lesser extent, on arachidonate (C20:4w6). We now report a new aspect of erythrocyte membrane structure; that is, phosphatidylethanolamine molecular species asymmetry. Polyunsaturated species containing arachidonate are preferentially localized on the cytoplasmic leaflet of the erythrocyte membrane. However, monoenoic species are more highly represented on the cell surface. Since alcohol causes a decline in polyunsaturated phospholipid species, we hypothesize a selective loss of membrane interior phospholipids. Conversely, dietary supplementation of omega-3 fatty acids led to increases in phospholipid species containing these acids that were localized to the membrane interior. Continued development of thermospray liquid chromatographic/mass spectrometric (LC/MS) techniques for phospholipid species has made possible a rapid, detailed and efficient analysis of all of the major lipid classes. Progress has been made in the quantification of phosphatidylcholines using deuterated internal standards. The biochemical characterization of the enzymatic oxygenation of 22:6w3 by rat brain homogenate was continued with respect to pH, enzyme inhibitors and various cofactors.