EFFECTS OF MEMBRANE FATTY ACIDS ON NEURONAL ION CHANNELS

亚麻酸（n-3）和亚麻酸（n-3）的多不饱和脂肪酸（PUFA） 亚油酸（n-3）类不是由动物合成的。 哺乳动物 组织不能相互转换不同类别的PUFA， 因此，从外生的衍生出n-3和n-6前体 源 神经组织的脂肪酸组成是高度 富含PUFA，含有相对大量的长- n-3类的链PUFA。 质膜的重要性 PUFA组成对神经元功能的影响仍然未知，尽管 有证据支持膜脂 会影响离子通道的功能 拟议研究的目的是检验这一假设 膜PUFA组成的变化可以影响神经元 通过改变被动膜特性和/或 电压依赖性离子通道的特性。 采取方法是 无血清培养大鼠胚胎新皮层神经元 培养基中，并通过改变膜PUFA组成， 用n-3或n-6类PUFA补充培养物。 的 在PUFA中生长的神经元的电生理特性 将补充的培养基与在培养基中生长的神经元进行比较 不添加外源性脂肪酸或在培养基中 补充有饱和或单不饱和脂肪酸。 的 电生理特性的差异将是 与膜脂组成的差异相关。 的 将使用千兆封全细胞电压钳记录技术 来研究电生理特性和高压 液相色谱-质谱-气相色谱 将使用色谱法分析质膜脂质 混合物. 通过研究这个相对于 分离的原代培养物的简单系统将有助于 了解必需多不饱和脂肪酸的作用 及其代谢产物在神经元兴奋性中的作用更为复杂 哺乳动物大脑的研究。 这将作为一个重要的基线 我的长期研究目标是了解 表观遗传对膜兴奋性表达的调节 哺乳动物大脑神经元发育中的因素。 本研究将 增加我们对中枢神经系统神经元功能缺陷的理解 由产前和产后必需脂肪酸缺乏引起。

The polyunsaturated fatty acids (PUFA) of the linolenic (n-3) and linoleic (n-3) classes are not synthesized by animals. Mammalian tissues cannot interconvert the different classes of PUFA and must therefore derive both n-3 and n-6 precursors from exogeneous sources. The fatty acid composition of neural tissues is highly enriched in PUFA and contain a relatively large amount of long- chain PUFA of the n-3 class. The importance of plasma membrane PUFA composition on neuronal function remains unknown, although there is evidence to support the hypothesis that membrane lipids can affect ion channel functions. The objective of the proposed research is to test the hypothesis that changes in membrane PUFA composition can affect neuronal excitability by altering passive membrane properties and/or properties of voltage-dependent ion channels. The approach is to grow rat embryonic neocortical neurons in serum-free defined culture medium and to alter the membrane PUFA composition by supplementing the culture with the n-3 or n-6 classes of PUFA. The electrophysiological properties of neurons grown in PUFA supplemented media will be compared with neurons grown in medium without the addition of exogenous fatty acids or in medium supplemented with saturated or monounsaturated fatty acids. The differences in the electrophysiological properties will be correlated with differences in membrane lipid composition. The gigaseal whole cell voltage-clamp recording technique will be used to study the electrophysiological properties, and high pressure liquid chromotography combined with mass spectrometry and gas chromatography will be used analyze plasma membrane lipid composition. The information that will be gained from studying this relatively simple system of dissociated primary cultures will aid in the understanding of the role of essential polyunsaturated fatty acids and their metabolites in neuronal excitability in the more complex mammalian brain in vivo. This will serve as an important baseline study for my longer term research goal, which is to understand the regulation of expression of membrane excitability by epigenetic factors in developing mammalian brain neurons. This study will increase our understanding of the functional defects of CNS neurons induced by prenatal and postnatal essential fatty acid deficiency.