Laribi C, Legendre P, Dupouy B, Vincent J D, Simonnet G
Brain Res. 1985 Nov 11;347(1):94-103. doi: 10.1016/0006-8993(85)90892-3.
Characteristics of angiotensin II (AII) binding have been determined in cultured mouse spinal cord neurones using [125I]AII and [3H]AII. The Scatchard plot of equilibrium binding was curvilinear and could be described by postulating the existence of two different classes of independent binding sites (Kd1 = 0.43 nM, Bmax1 = 12.5 fmol/1.5 X 10(6) cells; Kd2 = 25.6 nM, Bmax2 = 220 fmol/1.5 X 10(6) cells). These values are in close agreement with the Kd values obtained from kinetic studies. The high affinity binding sites appeared to be similar to the single class of sites described in other studies. The relative inhibition potency of AII-related peptides was studied. Sar1,-Leu8-AII was the most potent in inhibiting specific AII binding. The characteristics of the two AII binding sites suggest that they correspond to two receptors as described in a previous electrophysiological approach using this model in our laboratory. Taken together, these data confirm that this model of neurones in primary culture is a unique and very attractive model of receptor studies. The classical criteria necessary for positive identification of a ligand-receptor have been satisfied: saturability, reversibility, specificity and most importantly correlation of the binding parameters and biological effects of AII.
利用[125I]血管紧张素II（AII）和[3H]AII，已在培养的小鼠脊髓神经元中确定了AII结合的特性。平衡结合的Scatchard图呈曲线状，可通过假定存在两类不同的独立结合位点来描述（Kd1 = 0.43 nM，Bmax1 = 12.5 fmol/1.5×10(6)个细胞；Kd2 = 25.6 nM，Bmax2 = 220 fmol/1.5×10(6)个细胞）。这些值与动力学研究获得的Kd值非常一致。高亲和力结合位点似乎与其他研究中描述的单一类位点相似。研究了AII相关肽的相对抑制效力。Sar1，-Leu8-AII在抑制特异性AII结合方面最有效。两个AII结合位点的特性表明，它们对应于我们实验室先前使用该模型的电生理方法中描述的两种受体。综上所述，这些数据证实，这种原代培养神经元模型是受体研究中一种独特且极具吸引力的模型。阳性鉴定配体-受体所需的经典标准已得到满足：可饱和性、可逆性、特异性，最重要的是AII结合参数与生物学效应的相关性。
