title: Radiosynthesis, cerebral distribution, and binding of [125I]-1-(p-iodophenyl)-3-(1-adamantyl)guanidine, a ligand for sigma binding sites.
abstract: An analog of 1,3-di-o-tolylguanidine (DTG), [125I]-labeled 1-(p-iodophenyl)-3-(1-adamantyl)guanidine (PIPAG), was synthesized as a potential ligand for cerebral sigma binding sites. Data from in vitro binding experiments and in vivo experiments on brain distribution suggested that PIPAG binds to sigma binding sites with high affinity (Kd in low nanomolar range) as determined by Scatchard analysis and relative potencies of sigma-specific drugs. Haloperidol had the highest potency to inhibit [125I]PIPAG binding. It was followed by DTG, BMY 14802, and (+)-N-allylnormetazocine. Compounds with high affinities for dopamine receptors (but low affinity for sigma binding sites), for opioid receptors, for nicotinic acetylcholine receptors, and for phencyclidine receptors were ineffective inhibitors of [125I]PIPAG binding.
authors: Addiction Research Center, National Institute on Drug Abuse, Baltimore, Maryland 21224.
authors: A S
authors: AS
authors: Kimes
authors: A A
authors: AA
authors: Wilson
authors: U
authors: U
authors: Scheffel
authors: B G
authors: BG
authors: Campbell
authors: E D
authors: ED
authors: London
mesh_terms: D000818:Animals; D001345:Autoradiography; D001665:Binding Sites; D001667:Binding, Competitive; D001921:Brain / Q000378:metabolism*; D006146:Guanidines / Q000138:chemical synthesis / Q000378:metabolism* / Q000493:pharmacokinetics; D006168:Guinea Pigs; D007462:Iodobenzenes / Q000138:chemical synthesis / Q000378:metabolism* / Q000493:pharmacokinetics; D008297:Male; D051379:Mice; D017480:Receptors, sigma / Q000378:metabolism*; D014018:Tissue Distribution
chemical_list: D006146:Guanidines; D007462:Iodobenzenes; D017480:Receptors, sigma; C078885:1-(4-iodophenyl)-3-(1-adamantyl)guanidine