受体Megalin和Cubilin在培养的Opossum肾近端小管细胞的表达

目的及方法 采用Western印迹法及免疫细胞化学双标记法检测肾近端小管培养的OK细胞株上受体egalin及cubilin的表达及分布。结果 受 体megalin及cubilin在分离的OK细胞膜上有所表达，并且，应用megalin及cubilin抗体的免疫细胞化学双标记法显示，它们分布在细胞内顶部胞质的细胞内吞系统，包括微毛根部的有被小凹、胞内的有被吞饮小泡、大泡、溶酶体及参与细胞膜再循环的顶部致密小管。结论 这一分布特征提示，两种大分子糖蛋白受体与肾近端小管上皮细胞受体介导的细胞内吞功能有关。由于其分布极其接近，很可能在一些大分子的重吸收中起到相互作用。

Expression of Megalin and Cubilin in Cultured Proximal Tubule Cells of Opossum Kidney

Objective and methods In present study,using western blotting and immunocytochemistry we examined the colocalization of two giant glycoprotein receptors,megalin and cubilin,in cultured proximal tubule cells of opossum kidney(OK) Results The expression of both megalin and cubilin on purified membranes of OK cells was analyzed by Western blotting using polyclonal anti-megalin and -cubilin antibodies The subcellular colocalization of megalin and cubilin was demonstrated by a double-labeling immunocytochemistry technique Both receptors were similarly distributed at microvillus areas and often concentrated in clathrin-coated pits,invaginations at the apical cell membrane and in small and large endocytic vacuoles,as well as in dense apical tubules Conclusion The present study demonstrates membrane-associated megalin and cubilin in OK cells and established their subcellular colocalization,thereby to identify a suitable model system to study the receptor-receptor interaction to assist to the intake of their ligands