Differences between central and peripheral rat alpha-adrenoceptors revealed using binuclear ligands.
We have used two homologous series of binuclear ligands, diacridines and diquinolines, and the radioligand receptor assay to compare the topology of alpha 1- and alpha 2-adrenoceptors in rat cerebral cortex and kidney membranes. While the chain length-dependence of affinity of the diacridines, as well as that of the diquinolines, for the alpha 1-adrenoceptors of these central and peripheral tissues are similar, we find marked differences in affinity profiles for interaction with central and peripheral alpha 2-adrenoceptors. In the context of our previously proposed model for the binding of diacridines and diquinolines to alpha-adrenoceptors the results suggest that the surface features of central and peripheral alpha 2-adrenoceptors differ in the area surrounding the noradrenaline binding site. This difference may prove to be of therapeutic relevance.
D000166:Acridines / Q000378:metabolism; D000818:Animals; D001667:Binding, Competitive; D002540:Cerebral Cortex / Q000378:metabolism*; D005260:Female; D066298:In Vitro Techniques; D007668:Kidney / Q000378:metabolism*; D011224:Prazosin / Q000378:metabolism; D011804:Quinolines / Q000378:metabolism; D011869:Radioligand Assay; D051381:Rats; D011919:Rats, Inbred Strains; D011942:Receptors, Adrenergic, alpha / Q000378:metabolism*; D015016:Yohimbine / Q000378:metabolism
D000166:Acridines; D011804:Quinolines; D011942:Receptors, Adrenergic, alpha; D015016:Yohimbine; D011224:Prazosin