Haskell J F, Meezan E, Pillion D J
Endocrinology. 1984 Aug;115(2):698-704. doi: 10.1210/endo-115-2-698.
The presence of specific, high affinity receptors for insulin has been demonstrated in purified preparations of bovine retinal microvessels. The binding of [125I]insulin to isolated retinal microvessels was inhibited by unlabeled insulin, but not by other peptide hormones. Scatchard analysis of the [125I]insulin binding data gave a curvilinear plot similar to that exhibited by insulin receptors in known insulin-sensitive tissues such as adipocytes and hepatocytes. Binding of [125I]insulin to retinal microvessels, followed by covalent cross-linking of the bound ligand to the alpha-subunit of the insulin receptor with the bifunctional reagent disuccinimidyl suberate, yielded a prominent specific [125I]insulin-labeled band when analyzed by sodium dodecyl sulfate-gel electrophoresis followed by autoradiography, and this band had a mobility identical to that of the corresponding complex obtained with rat liver plasma membranes (mol wt, 125,000). These results demonstrate for the first time that the retinal microvasculature, a major site of pathological injury in diabetes mellitus, contains insulin receptors that are similar to those present in known insulin-sensitive tissues, such as liver, fat, and muscle.
在纯化的牛视网膜微血管制剂中已证实存在胰岛素的特异性高亲和力受体。[125I]胰岛素与分离的视网膜微血管的结合受到未标记胰岛素的抑制，但不受其他肽类激素的抑制。对[125I]胰岛素结合数据进行Scatchard分析得到的曲线与已知胰岛素敏感组织（如脂肪细胞和肝细胞）中胰岛素受体呈现的曲线相似。[125I]胰岛素与视网膜微血管结合后，用双功能试剂辛二酸二琥珀酰亚胺酯将结合的配体与胰岛素受体的α亚基进行共价交联，经十二烷基硫酸钠 - 凝胶电泳后进行放射自显影分析，得到一条突出的特异性[125I]胰岛素标记带，该带的迁移率与用大鼠肝细胞膜获得的相应复合物相同（分子量为125,000）。这些结果首次证明，视网膜微血管系统作为糖尿病病理损伤的主要部位，含有与已知胰岛素敏感组织（如肝脏、脂肪和肌肉）中存在的胰岛素受体相似的受体。
