Park C H, Massari V J, Quirion R, Tizabi Y, Shults C W, O'Donohue T L
Peptides. 1984 Jul-Aug;5(4):833-6. doi: 10.1016/0196-9781(84)90031-7.
Binding characteristics of 3H-Substance P (SP) were studied with rat brain membranes using a method applied to peripheral tissues by Lee and Snyder [15]. This method was well applicable to central nervous system (CNS) tissues. The results in the present study indicate that specific 3H-SP binding reaches a plateau only after 20 minutes of incubation, and the binding sites are saturable at a relatively low concentration of 3H-SP. Scatchard analysis of specific binding data reveals a single class of binding sites with a high affinity (Kd = 0.30 nM) and a low density (Bmax = 27.7 fmol/mg protein) in rat brain membranes. A Hill plot of the displacement curve of 3H-SP with unlabelled SP showed no indication for cooperativity (nH = 0.83). The relative potencies of binding of various SP fragments at 3H-SP binding sites were fairly parallel to the length of the C-terminal fragments. Neurotransmitters not structurally related to SP produced no effect on 3H-SP binding even when used at micromolar concentrations.
采用Lee和Snyder[15]应用于外周组织的方法，研究了大鼠脑膜中3H-物质P（SP）的结合特性。该方法非常适用于中枢神经系统（CNS）组织。本研究结果表明，特异性3H-SP结合仅在孵育20分钟后达到平台期，并且结合位点在相对较低浓度的3H-SP下即可饱和。对特异性结合数据进行Scatchard分析显示，大鼠脑膜中存在一类具有高亲和力（Kd = 0.30 nM）和低密度（Bmax = 27.7 fmol/mg蛋白）的结合位点。用未标记的SP对3H-SP的置换曲线进行Hill作图，未显示协同性迹象（nH = 0.83）。各种SP片段在3H-SP结合位点的结合相对效力与C末端片段的长度相当平行。即使以微摩尔浓度使用，与SP结构无关的神经递质对3H-SP结合也没有影响。
