Sphingolipids consist of a sphingoid base N-linked to a fatty acyl chain. Among them, sphingomyelins (SM) are major components of mammalian cells, while ceramide (Cer) plays an important role as a lipid second messenger. We have performed a quantitative lipidomic study of Cer and SM species in different mammalian tissues (adipose tissue, liver, brain and blood serum of human, mice, rat and dog), as well as in cell cultures of mammalian origin (primary hepatocytes, immortalized MDCK cells, mice melanoma b16 cells, and mice primary CD4 + T lymphocytes) using an ultra-high performance liquid chromatography coupled to time-of-flight mass spectrometry (UHPLC-ToF-MS)-based platform. The data have been compared with published, in general semi-quantitative, results from 20 other samples, with good agreement. The sphingoid base was predominantly d18-1 sphingosine (2-amino-4-octadecene-1,3-diol) in all cases. The fatty acid composition of SM was clearly different from that of Cer. In virtually all samples the most abundant Cer species were those containing C24:0 and C24:1 in their N-acyl chains, while the main species contained in SM was C16:0. Brain was the most divergent tissue, in which Cer and SM C18:0 were very abundant.

鞘脂由N-连接至脂肪酰基链的鞘脂碱基组成。其中，鞘磷脂（SM）是哺乳动物细胞的主要成分，而神经酰胺（Cer）作为脂质的第二信使起着重要的作用。我们对不同哺乳动物组织（人类，小鼠，大鼠和狗的脂肪组织，肝脏，脑和血清）以及哺乳动物起源的细胞培养物（原代肝细胞，永生化）中的Cer和SM物种进行了定量脂质组学研究MDCK细胞，小鼠黑色素瘤b16细胞和小鼠原代CD4 + T淋巴细胞）使用超高效液相色谱仪结合基于飞行时间质谱（UHPLC-ToF-MS）的平台进行分析。将数据与其他20个样本的结果（一般为半定量）进行了比较，结果吻合良好。在所有情况下，鞘氨醇碱主要为d18-1鞘氨醇（2-氨基-4-十八碳烯-1,3-二醇）。SM的脂肪酸组成与Cer明显不同。在几乎所有样品中，最丰富的Cer物种是在其N-酰基链中包含C24：0和C24：1的物种，而SM中包含的主要物种是C16：0。脑是最分散的组织，其中Cer和SM C18：0非常丰富。