Identification and pharmacological profile of a new class of selective nicotinic acetylcholine receptor potentiators

Lisa M Broad, Ruud Zwart, Kathy H Pearson, Martin Lee, Louise Wallace, Gordon I McPhie, Renee Emkey, Sean P Hollinshead, Colin P Dell, S Richard Baker, Emanuele Sher

Research output: Contribution to journalArticlepeer-review

Abstract

Here we report the discovery, by high-throughput screening, of three novel (2-amino-5-keto)thiazole compounds that act as selective potentiators of nicotinic acetylcholine receptors. Compound selectivity was assessed at seven human nicotinic acetylcholine receptors (alpha1beta1gammadelta, alpha2beta4, alpha3beta2, alpha3beta4, alpha4beta2, alpha4beta4, and alpha7) expressed in mammalian cells or Xenopus oocytes. At alpha2beta4, alpha4beta2, alpha4beta4, and alpha7, but not alpha1beta1gammadelta, alpha3beta2, or alpha3beta4, submaximal responses to nicotinic agonists were potentiated in a concentration-dependent manner by all compounds. At similar concentrations, no potentiation of 5-hydroxytryptamine, alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid, GABA(A), and N-methyl-d-aspartate receptors or voltage-gated Na(+) and Ca(2+) channels was observed. Furthermore, these compounds did not inhibit acetylcholine esterase. Further profiling revealed that these compounds enhanced the potency and maximal efficacy of a range of nicotinic agonists at alpha4beta2 nicotinic acetylcholine receptors, a profile typical of allosteric potentiators. At concentrations required for potentiation, the compounds did not displace [(3)H]epibatidine from the agonist-binding site, and potentiation was observed at all agonist concentrations, suggesting a noncompetitive mechanism of action. Blockade of common second messenger systems did not affect potentiation. At concentrations higher then required for potentiation the compounds also displayed intrinsic agonist activity, which was blocked by competitive and noncompetitive nicotinic acetylcholine receptor (nAChR) antagonists. These novel selective nicotinic receptor potentiators should help in clarifying the potential therapeutic utility of selective nAChR modulation for the treatment of central nervous system disorders.

Original languageEnglish
Pages (from-to)1108-17
Number of pages10
JournalJournal of pharmacology and experimental therapeutics
Volume318
Issue number3
DOIs
Publication statusPublished - Sep 2006

Keywords

  • Animals
  • Bicyclo Compounds, Heterocyclic
  • Cell Line
  • Drug Synergism
  • Galantamine
  • Humans
  • Nicotinic Agonists
  • Protein Subunits
  • Pyridines
  • Receptors, Nicotinic
  • Recombinant Proteins
  • Xenopus laevis

Fingerprint

Dive into the research topics of 'Identification and pharmacological profile of a new class of selective nicotinic acetylcholine receptor potentiators'. Together they form a unique fingerprint.

Cite this