Specific binding of alpha-bungarotoxin to synaptic membranes in rat sympathetic ganglion: computer best-fit analysis of electron microscope radioautographs.
Specific binding of alpha-bungarotoxin to synaptic membranes in rat sympathetic ganglion: computer best-fit analysis of electron microscope radioautographs.
复制标题
α-银环蛇毒素与大鼠交感神经节突触膜的特异性结合：电子显微镜放射自拍照的计算机最佳拟合分析。
DOI：
10.1016/0006-8993(83)90018-5
复制
发表时间：
1983
期刊：
影响因子：
2.9
通讯作者：
Smolen,AJ
中科院分区：
文献类型：
--
作者：
Smolen,AJ
In the rat superior cervical sympathetic ganglion (SCG), α-bungarotoxin (αBT) demonstrates binding that is saturable and inhibited by nicotinic ligands. However, αBT does not inhibit the physiological response of ganglionic neurons to preganglionic stimulation or to exogenously applied acetylcholine. Thus the specificity of αBT for ganglionic nicotinic cholinergic receptors has been questioned. The present study provides a morphological localization of the binding sites of125I-labelled αBT in the rat SCG using the method of Blackett and Parry on electron microscopic radioautographs. The distribution of grains resulting from specific binding was calculated by substracting the nonspecific distribution (αBT in the presence ofd-tubocurarine, a known nicotinic ligand) from the total grain distribution (αBT alone). A hypothetical grain distribution was obtained based on the geometrical properties of the tissue sections. A computer minimizing routine was employed to adjust the relative weights of each of the potential sources of hypothetical grains until a ‘best-fit’ with the real grain distributions occurred. The nonspecific binding of αBT was uniform across all tissue components, with the exception of a significant concentration on the membrane of the ganglion cell body. By contrast, the specific binding of αBT was highly localized to synaptic membranes, and to a lesser extent, to dendritic membranes.
