/sup 125/I-spiperone: a novel ligand for D/sub 2/ dopamine receptors

Journal Article · Mon Nov 05 04:00:00 EST 1984 · Life Sci.; (United States)

DOI:https://doi.org/10.1016/0024-3205(84)90479-X· OSTI ID:6168691

Gundlach, A L; Largent, B L; Synder, S H

/sup 125/I-Spiperone binds with high affinity K/sub D/ 0.3 nM) to a single specific site (B/sub max/ 34 pmole/g wet weight) in homogenates of rat corpus striatum. Specific binding is about 40-60 percent of total binding and is displaced stereo-specifically by butaclamol and clopenthixol. Neuroleptic drugs of various classes are potent inhibitors of /sup 125/I-spiperone binding (/sub i/'s 1-10 nM). Selective dopamine antagonists such as sulpiride (K/sub i/ 50 nM) and dopamine agonists such as apomorphine (K/sub i/ 200 nM) are also potent inhibitors. The drugs specificity of /sup 125/I-spiperone binding correlates well with that of /sup 3/H-spiperone binding, providing good evidence that /sup 125/I-spiperone labels D/sub 2/ dopamine receptors in striatal membranes. /sup 125/I-Spiperone, with its high specific activity (2200 Ci/mmol) may prove to be a useful ligand in studies examining D/sub 2/ dopamine receptors in soluble preparations and by autoradiography. Furthermore iodinated spiperone may be useful in radioreceptor assays of neuroleptic drug levels and, in a /sup 123/I-labeled form for imaging of dopamine receptors, in vivo, using single photon tomography. 18 references, 4 figures, 1 table.

• Research Organization: Johns Hopkins Univ., Baltimore, MD
• OSTI ID: 6168691
• Journal Information: Life Sci.; (United States), Journal Name: Life Sci.; (United States) Vol. 35:19; ISSN LIFSA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AFFINITY
AMINES
ANIMALS
ANTIDEPRESSANTS
AROMATICS
AUTONOMIC NERVOUS SYSTEM AGENTS
BETA DECAY RADIOISOTOPES
BIOCHEMICAL REACTION KINETICS
BODY
BRAIN
CARDIOTONICS
CARDIOVASCULAR AGENTS
CENTRAL NERVOUS SYSTEM
CENTRAL NERVOUS SYSTEM AGENTS
CHEMICAL BONDS
DAYS LIVING RADIOISOTOPES
DOPAMINE
DRUGS
ELECTRON CAPTURE RADIOISOTOPES
HOMOGENATES
HYDROXY COMPOUNDS
INTERMEDIATE MASS NUCLEI
IODINE 125
IODINE ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
KINETICS
LABELLED COMPOUNDS
LIGANDS
MAMMALS
NERVOUS SYSTEM
NEUROREGULATORS
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANS
PHENOLS
POLYPHENOLS
PSYCHOTROPIC DRUGS
RADIOASSAY
RADIOISOTOPES
RATS
REACTION KINETICS
RECEPTORS
RODENTS
SPECIFICITY
SYMPATHOMIMETICS
TRACER TECHNIQUES
VERTEBRATES