Solubilization and identification of human placental endothelin receptor.
Solubilization and identification of human placental endothelin receptor.
复制标题
人胎盘内皮素受体的溶解和鉴定。
DOI：
10.1016/0006-291x(89)91703-8
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发表时间：
1989
影响因子：
3.1
通讯作者：
Inagami,T
中科院分区：
文献类型：
--
作者：
Nakajo,S;Sugiura,M;Snajdar,RM;Boehm,FH;Inagami,T
摘要在人胎盘膜上鉴定出内皮素-1 （ET-1）受体，0.75%(w v) CHAPS可溶解66%的内皮素-1受体。用125 I-ET-1对溶解膜的结合研究表明，存在一类高亲和力的结合位点，表观Kd为760 pM， Bmax为1.8 pmol/mg蛋白质。未标记的ET-1和ET-3以剂量依赖的方式抑制其结合。溶解膜对ET-1的Ki值为84 pM，对ET-3的Ki值为250 pM，而颗粒膜对ET-1的Ki值为410 pM，对ET-3的Ki值为2500 pM。钙通道阻滞剂如硝地平、维拉帕米和地尔硫卓不影响125 I-ET-1的结合。用CHAPS对颗粒膜和溶解膜进行亲和标记，发现了一个Mr为32,000的特异性结合蛋白。
Abstract Endothelin-1 (ET-1) receptor was identified on the membranes from human placenta and 66% of original binding activity in the membranes was solubilized with 0.75%(w v) CHAPS. Binding studies of the solubilized membranes using 125 I-ET-1 indicated the presence of a single class of high-affinity binding sites with an apparent Kd of 760 pM and a Bmax of 1.8 pmol/mg of protein. The binding was inhibited by addition of unlabeled ET-1 and ET-3 in dose dependent manner. The Ki values of solubilized membranes were 84 pM for ET-1 and 250 pM for ET-3, whereas particulate membranes had weaker affinities (Ki= 410 pM for ET-1, 2500 pM for ET-3). Calcium channel blockers such as nicardipine, verapamil and diltiazem did not affect the binding of 125 I-ET-1. Affinity labeling of the particulate and solubilized membranes with CHAPS revealed a specific binding protein with a Mr of 32,000.