Click here to close Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly. We suggest using a current version of Chrome, FireFox, or Safari.
XB-ART-37680
Neuropharmacology 2008 Jun 01;548:1189-200. doi: 10.1016/j.neuropharm.2008.03.010.
Show Gene links Show Anatomy links

Extending the analysis of nicotinic receptor antagonists with the study of alpha6 nicotinic receptor subunit chimeras.

Papke RL , Dwoskin LP , Crooks PA , Zheng G , Zhang Z , McIntosh JM , Stokes C .


???displayArticle.abstract???
Heterologous expression systems have increased the feasibility of developing selective ligands to target nicotinic acetylcholine receptor (nAChR) subtypes. However, the alpha6 subunit, a component in nAChRs that mediates some of the reinforcing effects of nicotine, is not easily expressed in systems such as the Xenopus oocyte. Certain aspects of alpha6-containing receptor pharmacology have been studied by using chimeric subunits containing the alpha6 ligand-binding domain. However, these chimeras would not be sensitive to an alpha6-selective channel blocker; therefore we developed an alpha6 chimera (alpha4/6) that has the transmembrane and intracellular domains of alpha6 and the extracellular domain of alpha4. We examined the pharmacological properties of alpha4/6-containing receptors and other important nAChR subtypes, including alpha7, alpha4beta2, alpha4beta4, alpha3beta4, alpha3beta2, and alpha3beta2beta3, as well as receptors containing alpha6/3 and alpha6/4 chimeras. Our data show that the absence or presence of the beta4 subunit is an important factor for sensitivity to the ganglionic blocker mecamylamine, and that dihydro-beta-erythroidine is most effective on subtypes containing the alpha4 subunit extracellular domain. Receptors containing the alpha6/4 subunit are sensitive to alpha-conotoxin PIA, while receptors containing the reciprocal alpha4/6 chimera are insensitive. In experiments with novel antagonists of nicotine-evoked dopamine release, the alpha4/6 chimera indicated that structural rigidity was a key element of compounds that could result in selectivity for noncompetitive inhibition of alpha6-containing receptors. Our data extend the information available on prototypical nAChR antagonists, and establish the alpha4/6 chimera as a useful new tool for screening drugs as selective nAChR antagonists.

???displayArticle.pubmedLink??? 18448138
???displayArticle.pmcLink??? PMC2494738
???displayArticle.link??? Neuropharmacology
???displayArticle.grants??? [+]


References [+] :
Ayers, bis-Azaaromatic quaternary ammonium analogues: ligands for alpha4beta2* and alpha7* subtypes of neuronal nicotinic receptors. 2002, Pubmed