Sodium-dependent high-affinity binding of [3H] hemicholinium-3 in the rat brain: A potentially selective marker for presynaptic cholinergic sites

Thomas W. Vickroy, William R. Roeske, Henry I. Yamamura

Research output: Contribution to journalArticle

91 Scopus citations

Abstract

This report describes the membrane binding properties of [3H] hemicholinium-3 ([3H]HC-3), a selective inhibitor of sodium-dependent high-affinity choline uptake (SDHACU) in cholinergic nerve terminals. Under the described assay conditions, [3H]HC-3 binds with a saturable population of high-affinity (apparent Kd=1.9 nM) CNS membrane sites having the regional distribution: striatum ≫ hippocampus > cerebral cortex > cerebellum. High-affinity [3H]HC-3 binding is entirely dependent upon the presence of sodium chloride (EC50=35-50 mM) and is markedly reduced when other salts of sodium or monovalent ions are substituted. [3H]HC-3 binding is inhibited by choline (Ki=6μM) and acetylcholine (Ki=35μM) but markedly less sensitive to other cholinergic agents and metabolic inhibitors. In light of the similar ionic dependencies, regional distributions and pharmacological specificities of [3H]HC-3 binding and SDHACU, closely associated sites may be involved in both processes.

Original languageEnglish (US)
Pages (from-to)2335-2343
Number of pages9
JournalLife Sciences
Volume35
Issue number23
DOIs
StatePublished - Dec 3 1984
Externally publishedYes

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)
  • Pharmacology, Toxicology and Pharmaceutics(all)

Fingerprint Dive into the research topics of 'Sodium-dependent high-affinity binding of [<sup>3</sup>H] hemicholinium-3 in the rat brain: A potentially selective marker for presynaptic cholinergic sites'. Together they form a unique fingerprint.

  • Cite this