Ligand binding to dopamine-receptors: Analysis & interpretation

Dopamine receptor interaction was studied by concentration dependent inhibition of ³H-Spiperone binding to calf caudate nucleus homogenates with (+)-butaclamol, haloperidol, ergometrine, apomorphine and dopamine. The results were analyzed in terms of a one and a two site receptor model using computerized curve fitting procedures. Evidence is given in favour of a two site receptor model on basis of statistical criteria. The presence of two independent non-interconverting receptor sites for dopamine in calf caudate nucleus is consistent with binding data from others and with in vivo experiments.