Itonori S, Shirai T, Kiso Y, Ohashi Y, Shiota K, Ogawa T
Laboratory of Cellular Biochemistry, University of Tokyo, Japan.
Biochem J. 1995 Apr 15;307 ( Pt 2)(Pt 2):399-405. doi: 10.1042/bj3070399.
The composition of glycolipids and their changes in the placenta were investigated in the normal pregnant rat. Total lipid fractions extracted from the placenta between days 12 and 20 of pregnancy (day 0 = oestrus) were subjected to glycolipid analysis using DEAE-Sephadex chromatography, silica-gel HPLC, silica-gel TLC, TLC/immunostaining, matrix-assisted secondary-ion mass spectrometry in the negative-ion mode and 1H NMR. Glycolipids identified in the rat placenta were: gangliosides GM3 (NeuAcLacCer and NeuGcLacCer) and GD3 (NeuAcNeuAcLacCer, NeuAcNeuGcLacCer and NeuGcNeuAcLacCer), and neutral glycolipids ceramide monosaccharide (CMH) (GlcCer), ceramide disaccharide (CDH) (LacCer), ceramide trisaccharide (CTH) (Gb3Cer) and ceramide tetrasaccharide (CQH) (Gb4Cer). The content of neutral glycolipids was higher than that of gangliosides throughout pregnancy. Of the neutral glycolipids, CMH and CTH predominated and the level of CDH was low at mid-pregnancy. During late pregnancy, CMH and CTH decreased and CDH increased markedly. CQH remained at a low level throughout pregnancy. Of the gangliosides, GM3 was predominant on days 12-16 and then decreased, whereas GD3, which was low on day 12, increased slightly on day 16 and maintained the same level thereafter. Immunohistochemical studies indicated that these changes in the expression of major gangliosides from GM3 to GD3 occurred in labyrinthine trophoblasts. Thus expression of these glycolipids appears to change markedly during pregnancy.
在正常妊娠大鼠中研究了胎盘糖脂的组成及其变化。从妊娠第12天至20天（第0天=发情期）的胎盘提取的总脂质部分，采用二乙氨基乙基葡聚糖柱色谱法、硅胶高效液相色谱法、硅胶薄层层析法、薄层层析/免疫染色法、负离子模式基质辅助二次离子质谱法和核磁共振氢谱进行糖脂分析。在大鼠胎盘中鉴定出的糖脂有：神经节苷脂GM3（NeuAcLacCer和NeuGcLacCer）和GD3（NeuAcNeuAcLacCer、NeuAcNeuGcLacCer和NeuGcNeuAcLacCer），以及中性糖脂神经酰胺单糖（CMH）（GlcCer）、神经酰胺二糖（CDH）（LacCer）、神经酰胺三糖（CTH）（Gb3Cer）和神经酰胺四糖（CQH）（Gb4Cer）。在整个孕期，中性糖脂的含量高于神经节苷脂。在中性糖脂中，CMH和CTH占主导地位，妊娠中期CDH水平较低。在妊娠后期，CMH和CTH减少，CDH显著增加。CQH在整个孕期保持在低水平。在神经节苷脂中，GM3在第12至16天占主导地位，然后减少，而GD3在第12天含量较低，在第16天略有增加，此后保持相同水平。免疫组织化学研究表明，这些主要神经节苷脂从GM3到GD3的表达变化发生在迷路滋养层细胞中。因此，这些糖脂的表达在孕期似乎发生了显著变化。
