Waggoner W G, Genova S L, Rash V A
Div. of Pharmacology, Wellcome Research Laboratories, Research Triangle Park, N.C. 27709.
Life Sci. 1992;51(24):1869-76. doi: 10.1016/0024-3205(92)90038-q.
The kinetics of [125I]Endothelin-1 ([125I]ET-1) binding were studied using membranes from rat heart, rat lung, rat brain, and porcine vascular smooth muscle at 37 degrees C in 0.05M Tris-HCl buffer (pH = 7.4). The dissociation half-life (t1/2, diss.) for bound [125I]ET-1 was in excess of 30 hours for each tissue studied. Equilibrium-time requirements for proper Scatchard analysis of [125I]ET-1 were also far in excess of 30 hours for each tissue. These data suggest that determination of dissociation constants, Kd, and receptor concentrations, Bmax, by conventional Scatchard analysis is not feasible with [125I]ET-1. Kinetic analyses may provide a more accurate means for determining [125I-ET-1] binding characteristics including Kd and Bmax.
在37摄氏度下，于0.05M Tris-HCl缓冲液（pH = 7.4）中，使用大鼠心脏、大鼠肺、大鼠脑以及猪血管平滑肌的膜来研究[125I]内皮素-1（[125I]ET-1）的结合动力学。对于所研究的每个组织，结合的[125I]ET-1的解离半衰期（t1/2，解离）超过30小时。对每个组织进行[125I]ET-1的正确Scatchard分析所需的平衡时间也远远超过30小时。这些数据表明，通过传统的Scatchard分析来确定解离常数Kd和受体浓度Bmax对于[125I]ET-1是不可行的。动力学分析可能为确定包括Kd和Bmax在内的[125I-ET-1]结合特性提供一种更准确的方法。
