Biomaterial Database

Radiosynthesis, cerebral distribution, and binding of [125I]-1-(p-iodophenyl)-3-(1-adamantyl)guanidine, a ligand for sigma binding sites. 1992

A S Kimes, and A A Wilson, and U Scheffel, and B G Campbell, and E D London

Addiction Research Center, National Institute on Drug Abuse, Baltimore, Maryland 21224.

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.

UI	MeSH Term	Description	Entries
D007462	Iodobenzenes	Any derivative of BENZENE that contains IODINE.
D008297	Male		Males
D001921	Brain	The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.	Encephalon
D006146	Guanidines	A family of iminourea derivatives. The parent compound has been isolated from mushrooms, corn germ, rice hulls, mussels, earthworms, and turnip juice. Derivatives may have antiviral and antifungal properties.
D006168	Guinea Pigs	A common name used for the genus Cavia. The most common species is Cavia porcellus which is the domesticated guinea pig used for pets and biomedical research.	Cavia,Cavia porcellus,Guinea Pig,Pig, Guinea,Pigs, Guinea
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001345	Autoradiography	The making of a radiograph of an object or tissue by recording on a photographic plate the radiation emitted by radioactive material within the object. (Dorland, 27th ed)	Radioautography
D001665	Binding Sites	The parts of a macromolecule that directly participate in its specific combination with another molecule.	Combining Site,Binding Site,Combining Sites,Site, Binding,Site, Combining,Sites, Binding,Sites, Combining
D001667	Binding, Competitive	The interaction of two or more substrates or ligands with the same binding site. The displacement of one by the other is used in quantitative and selective affinity measurements.	Competitive Binding
D014018	Tissue Distribution	Accumulation of a drug or chemical substance in various organs (including those not relevant to its pharmacologic or therapeutic action). This distribution depends on the blood flow or perfusion rate of the organ, the ability of the drug to penetrate organ membranes, tissue specificity, protein binding. The distribution is usually expressed as tissue to plasma ratios.	Distribution, Tissue,Distributions, Tissue,Tissue Distributions