SPECIFIC LABELING OF POSTSYNAPTIC ALPHA-1 ADRENOCEPTORS IN RAT-HEART VENTRICLE BY H-3-WB 4101

The α-adrenoceptor ligand, 3H-WB 4101 binds to a single population of independent sites in the rat heart ventricle. These sites are not affected by chemical sympathectomy with 6-hydroxydopamine and thus appear to be located postsynaptically. The relative order of potencies for displacement of 3H-WB 4101 binding: prazosin>phentolamine>yohimbine, is characteristic of that of the α1 type of adrenoceptors. In heart ventricle 3H WB-4101 thus seems to label specifically postsynaptically located α1-adrenoceptors. The significance of the specificity of this ligand is discussed with relevance to its use in the central nervous system. © 1979 Springer-Verlag.