title: Purines interact with 'central' but not 'peripheral' benzodiazepine binding sites.
abstract: The effects of several purines and the purine uptake inhibitor, dipyridamole, on the binding, to rat brain membranes, of 4 benzodiazepines with different pharmacological specificities were studied. While all purines tested displaced the binding of [3H](+)-3-methyl-clonazepam and [3H]Ro15-1788, selective agonist and antagonist ligands respectively for 'central' benzodiazepine receptors, purines had little or no affinity for [3H]Ro5-4864 'peripheral'-type binding sites in brain, heart or kidney. These results suggest that purines interact with a pharmacologically relevant class of central benzodiazepine 'receptors', and not with central and peripheral 'acceptor' sites labelled by the benzodiazepine Ro5-4864.
mesh_terms: D000818:Animals; D001570:Benzodiazepinones / Q000378:metabolism; D001667:Binding, Competitive; D001921:Brain / Q000378:metabolism*; D003975:Diazepam / Q000378:metabolism; D005442:Flumazenil; D011687:Purines / Q000378:metabolism*; D051381:Rats; D011956:Receptors, Cell Surface / Q000378:metabolism*; D011963:Receptors, GABA-A; D013574:Synaptosomes / Q000378:metabolism; D002998:Clonazepam / Q000031:analogs & derivatives
chemical_list: D001570:Benzodiazepinones; D003975:Diazepam; D005442:Flumazenil; D011687:Purines; D011956:Receptors, Cell Surface; D011963:Receptors, GABA-A; C028513:4'-chlorodiazepam; C020602:meclonazepam; D002998:Clonazepam