Specific 3H-DMCM binding to a non-benzodiazepine binding site after silver ion treatment of rat brain membranes.
Specific binding of the BZ-receptor ligand 3H-DMCM to rat cortical membranes was dramatically enhanced by preincubation of the homogenate with 0.1 mM silver (Ag+) nitrate. The binding was completely inhibited by midazolam. Nevertheless, the pharmacological specificity of the Ag+-enhanced 3H-DMCM binding was different from that of BZ-receptors. Furthermore, the Bmax value, the regional distribution and the molecular target size determined by radiation inactivation analysis of the Ag+-enhanced binding site were different from those of BZ-receptors. The results indicate that Ag+-enhanced 3H-DMCM binding represent a high affinity metal complex formation between 3H-DMCM and an unknown brain specific protein of approximately 100,000 daltons molecular weight.
D000818:Animals; D001569:Benzodiazepines / Q000378:metabolism; D001665:Binding Sites / Q000187:drug effects; D001667:Binding, Competitive; D001921:Brain / Q000378:metabolism*; D002243:Carbolines / Q000378:metabolism*; D005445:Flunitrazepam / Q000378:metabolism; D066298:In Vitro Techniques; D007211:Indoles / Q000378:metabolism*; D008566:Membranes / Q000187:drug effects / Q000378:metabolism; D008874:Midazolam; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D011485:Protein Binding / Q000187:drug effects; D051381:Rats; D011963:Receptors, GABA-A / Q000187:drug effects / Q000378:metabolism; D012834:Silver / Q000494:pharmacology*
D002243:Carbolines; D007211:Indoles; D009419:Nerve Tissue Proteins; D011963:Receptors, GABA-A; D001569:Benzodiazepines; C034818:methyl 6,7-dimethoxy-4-ethyl-beta-carboline-3-carboxylate; D012834:Silver; D005445:Flunitrazepam; D008874:Midazolam