METABOLIC AND STRUCTURAL STUDIES OF POLYUNSATURATED LIPIDS IN CELL MEMBRANES

主要目的是阐明结构和代谢。 具有特殊功能的多不饱和脂肪酸或磷脂 提到乙醇对它们的调节作用。实现这一目标的几种方法 问题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)和较小程度的花生四烯酸 C20：4w6)。 我们现在报道红细胞膜结构的一个新方面，即， 磷脂酰乙醇胺分子物种的不对称性。多不饱和 含有花生四烯酸的物种优先分布在 红细胞膜的细胞质小叶。然而，单烯酸 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 膜内磷脂的选择性损失。相反，饮食 补充omega-3脂肪酸导致磷脂增加 含有这些酸的物种，这些酸定位于膜内部。 热喷雾液相色谱/质谱联用的研究进展 磷脂物种的光谱(LC/MS)技术已成为可能 对所有主要脂质进行快速、详细和有效的分析 上课。在量化方面取得了进展 磷脂酰胆碱使用氚代内标物。 酶促氧化22：6W3的生化特性 大鼠脑匀浆在pH、酶抑制剂方面继续 以及各种辅因。

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.