Yamane M, Abe A, Nakajima M
Department of Biochemistry, Tokyo Medical College, Japan.
J Chromatogr B Biomed Appl. 1994 Dec 2;662(1):91-6. doi: 10.1016/0378-4347(94)00380-7.
A method for the analysis of omega-hydroxy polyunsaturated fatty acids (omega-HPUFAs) in rat tissue homogenate, supplemented with NADPH and homo-gamma-linolenic acid [20:3(n-6)], arachidonic acid [20:4(n-6)], eicosapentaenoic acid [20:5(n-3)] or docosahexaenoic acid [22:6(n-3)] as a substrate was developed. By ion analysis of chromatograms obtained with reversed-phase HPLC-thermospray MS, many omega-HPUFAs corresponding to each precursor fatty acid could be characterized by the high intensity of the molecular ion (MH+) and quasimolecular ion (MNH4+, MNa+), while other common HPUFAs were characterized by the high intensity of the base ion of MH+--H2O. On a selected-ion monitoring chromatogram of rat brain homogenate, significant amounts of omega-HPUFA from each precursor fatty acid, especially from 22:6(n-3), were detected compared with the amounts found in rat large intestine homogenate. Based on these results, a highly active NADPH-dependent omega-oxidation system is suggested for rat brain homogenate resulting in extensive oxidation of 22:6(n-3).
建立了一种分析大鼠组织匀浆中ω-羟基多不饱和脂肪酸（ω-HPUFAs）的方法，该方法以添加了烟酰胺腺嘌呤二核苷酸磷酸（NADPH）和同型γ-亚麻酸[20:3(n-6)]、花生四烯酸[20:4(n-6)]、二十碳五烯酸[20:5(n-3)]或二十二碳六烯酸[22:6(n-3)]作为底物。通过对反相高效液相色谱-热喷雾质谱法获得的色谱图进行离子分析，对应于每种前体脂肪酸的许多ω-HPUFAs可通过分子离子（MH+）和准分子离子（MNH4+、MNa+）的高强度来表征，而其他常见的HPUFAs则通过MH+–H2O的基峰离子的高强度来表征。在大鼠脑匀浆的选择离子监测色谱图上，与大鼠大肠匀浆中发现的量相比，检测到了来自每种前体脂肪酸的大量ω-HPUFA，尤其是来自22:6(n-3)的。基于这些结果，提示大鼠脑匀浆中存在一种高活性的依赖NADPH的ω-氧化系统，导致22:6(n-3)的广泛氧化。
