Histochemical studies on glycolipids especially from functional and developmental aspects

用激光共聚焦扫描显微镜和透射电镜观察了大鼠肾脏和小肠中各种糖脂的组织化学定位。从正常Wistar大鼠和糖尿病Goto-Kakizaki（GK）大鼠中分离样品，分别用抗globo苷（Gb3）或神经节苷（GM1、GD2、GQ1b、GD3、GD1a、GM3、o-乙酰基-GD3）的小鼠单克隆抗体（mab）处理，然后分别用cy3标记的二抗（共聚焦显微镜）和hrp标记的抗体（电镜）处理。在小肠中，一些神经节苷类物质（GD2、GQ1b等）在肌肠丛的神经细胞体周围以及内环平滑肌细胞的质膜上均有积累。肠腺上皮细胞，特别是其基底外侧质膜中glob苷（Gb3）阳性。在正常肾皮质中，每种抗体在肾小球和尿小管上皮细胞中表现出特定的分布模式。在GK大鼠中，与正常Wistar大鼠相比，抗gb3和抗gd1a抗体对肾小球的染色性增加。电镜观察显示，GK大鼠抗gb3的结合位点为肾小球基底膜、足细胞和内皮细胞的质膜。糖尿病大鼠肾皮质糖脂的特殊分布及其变化可能为了解肾功能特别是肾小球区域的功能提供重要线索。

Histochemical localizations of various kinds of glycolipids in rat kidney and small intestine were investigated with the use of confocal laser scanning microscopy and transmission electron microscopy. Samples were isolated from normal Wistar rats and diabetic Goto-Kakizaki(GK)rats and were treated with mouse monoclonal antibodies(mAbs) against globoside(Gb3) or gangliosides(GM1, GD2, GQ1b, GD3, GD1a, GM3, o-acetyl-GD3) followed by treatment with Cy3-labeled secondary antibody for confocal microscopy and HRP-labeled antibody for electron microscopy, respectively. In the case of small intestine, accumulations of some gangliosides (GD2, GQ1b etc.) were observed around the nerve cell body in the myenteric plexus and also along the plasma membranes of inner-circular smooth muscle cells. Intestinal gland epithelial cells, especially their basolateral plasma membranes were positive for globoside (Gb3). In normal kidney cortex, each antibody revealed specific distribution pattern especially in glomeruli and in urinary tubular epithelial cells. In GK rats, anti-Gb3 and anti-GD1a antibodies demonstrated increased stainability for glomeruli compared with those in normal Wistar rats. Electron microscopical observation revealed that, the binding sites of anti-Gb3 in GK rats were glomerular basement membranes and the plasma membranes of podocytes and endothelial cells. Specific distributions of glycolipids in rat kidney cortex and their changes following diabetic disorder may provide some important clues for understanding renal functions especially in glomerular area.