Gastrin receptor characterization: affinity cross-linking of the gastrin receptor on canine gastric parietal cells.
Gastrin receptor characterization: affinity cross-linking of the gastrin receptor on canine gastric parietal cells.
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胃泌素受体表征：胃泌素受体在犬胃壁细胞上的亲和交联。
DOI：
10.1152/ajpgi.1987.252.1.g143
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发表时间：
1987
期刊：
影响因子：
--
通讯作者：
Yamada,T
中科院分区：
文献类型：
--
作者：
Matsumoto,M;Park,J;Yamada,T
为了阐明胃泌素受体的化学结构性质，应用亲和交联方法对分离的犬胃壁细胞进行了胃泌素受体的标记。125i标记的Leu15-gastrin和125i标记的gastrin2（-17）以相同的亲和力与完整的壁细胞及其膜结合，并且在3.2 X 10(-10) M未标记的胃泌素的孵育浓度下获得半最大的结合抑制。125i -胃泌素2（-17）通过在二琥珀酰亚硝酸盐中孵育与质膜或完整的壁细胞交联。用二硫苏糖醇或不加二硫苏糖醇对膜球进行溶解，并在7.5%十二烷基硫酸钠聚丙烯酰胺凝胶上进行电泳。放射自显像显示在Mr 76,000处有一个标记带，并且在孵育混合物中加入未标记的胃泌素以剂量依赖性的方式抑制该标记带的标记。浓度高达100 mM的二硫苏糖醇不会改变标记带的电泳迁移率。在考虑了125i -胃泌素2（-17）的分子量后，我们的研究结果表明，壁细胞上的胃泌素受体是一个Mr为74,000的单一蛋白，不含二硫连接亚基。
We applied affinity cross-linking methods to label the gastrin receptor on isolated canine gastric parietal cells in order to elucidate the nature of its chemical structure. 125I-labeled Leu15-gastrin and 125I-labeled gastrin2(-17) bound to intact parietal cells and their membranes with equal affinity, and half-maximal inhibition of binding was obtained at an incubation concentration of 3.2 X 10(-10) M unlabeled gastrin. 125I-gastrin2(-17) was cross-linked to plasma membranes or intact parietal cells by incubation in disuccinimidyl suberate. The membrane pellets were solubilized with or without dithiothreitol and applied to electrophoresis on 7.5% sodium dodecyl sulfate polyacrylamide gels. Autoradiograms revealed a band of labeling at Mr 76,000 and labeling of this band was inhibited in a dose-dependent fashion by addition of unlabeled gastrin to the incubation mixture. Dithiothreitol in concentrations as high as 100 mM did not alter the electrophoretic mobility of the labeled band. After taking into account the molecular weight of 125I-gastrin2(-17), our results suggest that the gastrin receptor on parietal cells is a single protein of Mr 74,000 without disulfide-linked subunits.