University of Leipzig, Faculty of Medicine, Institute of Medical Physics and Biophysics, Härtelstrasse 16-18, D-04107 Leipzig, Germany.
Rapid Commun Mass Spectrom. 2011 Sep 30;25(18):2619-26. doi: 10.1002/rcm.5161.
The liver is an important organ that is particularly involved in the lipid metabolism of the organism. Thus, high interest is nowadays focused on the lipid composition of the liver and particularly the liver parenchymal cells, the hepatocytes. Hepatocytes contain common phospholipids (PL) such as phosphatidylcholines, -ethanolamines and -inositols, for instance, that can be easily analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) even without previous separation of the PL mixture. However, in addition to common PL, hepatocytes possess also significant amounts of cardiolipin (CLP). The MS analysis of this PL is quite challenging because it (a) has a higher mass than common lipids and (b) possesses a higher negative charge. We will show here that caution is required if CLP is analyzed directly from the total lipid extract because PC dimers may be interpreted as cardiolipins if the positive ion MALDI mass spectra are analyzed.
肝脏是一个重要的器官，它特别参与生物体的脂质代谢。因此，人们现在对肝脏的脂质组成，特别是肝实质细胞（肝细胞）中的脂质组成非常感兴趣。肝细胞含有常见的磷脂（PL），如磷脂酰胆碱、磷脂酰乙醇胺和磷脂酰肌醇等，即使不预先分离 PL 混合物，也可以通过基质辅助激光解吸/电离飞行时间质谱（MALDI-TOF MS）轻松分析。然而，除了常见的 PL 之外，肝细胞还含有大量的心磷脂（CLP）。这种 PL 的 MS 分析具有一定的挑战性，因为它 (a) 分子量比常见脂质高，(b) 带有更高的负电荷。我们将在这里表明，如果直接从总脂质提取物中分析 CLP，需要谨慎，因为如果分析正离子 MALDI 质谱，则 PC 二聚体可能被解释为心磷脂。
