Rösen P, Ehrich B, Junger E, Bubenzer H J, Kühn L
Biochim Biophys Acta. 1979 Nov 1;587(4):593-605. doi: 10.1016/0304-4165(79)90011-4.
With the large-scale preparation described, as much as 1 kg of bovine liver can be processed, giving a yield of more than 1 g plasma membrane protein. From analytical and morphological criteria the plasma membrane fraction isolated mainly derives from bile-canalicular and contiguous areas of the hepatocytes. The insulin binding activity is quite similar to insulin receptors in other cell systems and membrane preparations. Insulin-degrading activity is very low in the isolated plasma fraction. Most of degrading activity is located in a microsomal membrane fraction. Nevertheless the Km and the pH dependence of the insulin-degrading activity in both fractions are nearly identical. From these studies we conclude that binding and degradation of insulin are two independent processes located on different cell organelles.
通过所述的大规模制备方法，可处理多达1千克的牛肝，得到超过1克的质膜蛋白。从分析和形态学标准来看，分离出的质膜部分主要来源于肝细胞的胆小管及相邻区域。胰岛素结合活性与其他细胞系统和膜制剂中的胰岛素受体非常相似。在分离出的质膜部分中，胰岛素降解活性非常低。大部分降解活性位于微粒体膜部分。然而，两个部分中胰岛素降解活性的米氏常数（Km）和pH依赖性几乎相同。从这些研究中我们得出结论，胰岛素的结合和降解是位于不同细胞器上的两个独立过程。
