cis-Methyldioxolane specifically recognizes the m2 muscarinic receptor.


Journal Article

cis-Methyldioxolane (CD) is a muscarinic receptor agonist. [3H]CD has been used to label a subpopulation of muscarinic receptors described as exhibiting high agonist affinity. Pharmacological evidence suggests that the population of receptors labeled by [3H]CD consists of m2 and/or m4 subtypes; however, no studies have directly addressed the subtype selectivity of [3H]CD. The present study characterizes binding of this ligand to individual human receptor subtypes expressed in transfected Chinese hamster ovary cells. Results indicate that [3H]CD binds with high affinity only to Hm2 receptors but not to all Hm2 receptors. Twenty-eight percent of Hm2 receptors bound [3H]CD with a KD of 3.5 +/- 0.5 nM. Binding was eliminated in the presence of guanosine 5'-O-(3-thiotriphosphate), indicating that the Hm2 receptors labeled by [3H]CD are those that are associated with GDP-bound G protein. Binding of [3H]CD by only a subpopulation of Hm2 receptors is in agreement with data generated from studies of [3H]CD binding in mammalian brain. Because muscarinic receptors have been implicated to play a role in the pathogenesis of both Alzheimer's and Parkinson's disease, as well as the neurotoxicity of organophosphorus compounds, knowledge of the binding specificity of the muscarinic agonist [3H]CD should aid research in these areas.

Full Text

Duke Authors

Cited Authors

  • Huff, RA; Abou-Donia, MB

Published Date

  • January 1, 1994

Published In

Volume / Issue

  • 62 / 1

Start / End Page

  • 388 - 391

PubMed ID

  • 8263542

Pubmed Central ID

  • 8263542

International Standard Serial Number (ISSN)

  • 0022-3042

Digital Object Identifier (DOI)

  • 10.1046/j.1471-4159.1994.62010388.x


  • eng

Conference Location

  • England