Haskell J F, Pillion D J, Meezan E
WJB Dorn Veterans Administration Hospital, Columbia, South Carolina.
Endocrinology. 1988 Aug;123(2):774-80. doi: 10.1210/endo-123-2-774.
Rat renal glomeruli were isolated by a technique involving kidney perfusion with a solution containing magnetic iron oxide particles, followed by homogenization, sieving, and concentration over a strong magnet. Isolated glomeruli were treated with 1% Triton X-100 to solubilize plasma membrane components, while insoluble basement membrane components were removed by centrifugation. [125I]Insulin-like growth factor II (IGF-II) binding to this preparation was competitively inhibited by increasing amounts of unlabeled IGF-II, with 50% inhibition at an IGF-II concentration of 1 ng/ml. [125I]IGF-II was covalently cross-linked with disuccinimidyl suberate to its receptor in rat renal glomeruli and a specific high mol wt (255,000) band could be identified on autoradiograms of dodecyl sulfate-polyacrylamide gels. [125I]IGF-II binding and cross-linking to this band was inhibited by a polyclonal antibody against the type II IGF receptor. These results demonstrate for the first time that the isolated rat renal glomerulus contains a high affinity receptor for IGF-II.
通过一种技术分离大鼠肾肾小球，该技术包括用含有磁性氧化铁颗粒的溶液灌注肾脏，随后进行匀浆、筛分，并通过强磁体进行浓缩。将分离的肾小球用1% Triton X - 100处理以溶解质膜成分，同时通过离心去除不溶性基底膜成分。随着未标记的胰岛素样生长因子II（IGF - II）量的增加，[125I]IGF - II与该制剂的结合受到竞争性抑制，在IGF - II浓度为1 ng/ml时抑制率为50%。[125I]IGF - II与辛二酸二琥珀酰亚胺酯共价交联至大鼠肾肾小球中的受体，并且在十二烷基硫酸钠 - 聚丙烯酰胺凝胶的放射自显影片上可鉴定出一条特定的高分子量（255,000）条带。针对II型IGF受体的多克隆抗体抑制了[125I]IGF - II与该条带的结合和交联。这些结果首次证明分离的大鼠肾肾小球含有IGF - II的高亲和力受体。
