Title : Stable expression and pharmacological properties of the human alpha 7 nicotinic acetylcholine receptor - Gopalakrishnan_1995_Eur.J.Pharmacol_290_237 |
Author(s) : Gopalakrishnan M , Buisson B , Touma E , Giordano T , Campbell JE , Hu IC , Donnelly-Roberts D , Arneric SP , Bertrand D , Sullivan JP |
Ref : European Journal of Pharmacology , 290 :237 , 1995 |
Abstract :
The alpha 7 neuronal nicotinic acetylcholine receptor subtype forms a Ca(2+)-permeable homooligomeric ion channel sensitive to alpha-bungarotoxin in Xenopus oocytes. In this study, we have stably and functionally expressed the human alpha 7 cDNA in a mammalian cell line, HEK-293 and examined its pharmacologic properties. [125I] alpha-Bungarotoxin bound to transfected cells with a Kd value of 0.7 nM and a Bmax value of 973 pmoL/mg protein. No specific binding was detected in untransfected cells. Specific binding could be displaced by unlabeled alpha-bungarotoxin (Ki = 0.5 nM) and an excellent correlation was observed between binding affinities of a series of nicotinic cholinergic ligands in transfected cells and those in the human neuroblastoma IMR-32 cell line. Additionally, cell surface expression of alpha 7 receptors was detected by fluorescein isothiocyanate-conjugated alpha-bungarotoxin in transfected cells. Whole cell currents sensitive to blockade by alpha-bungarotoxin, and with fast kinetics of activation and inactivation, were recorded from transfected cells upon rapid application of (-)-nicotine or acetylcholine with EC50 values of 49 microM and 155 microM respectively. We conclude that the human alpha 7 subunit when expressed alone can form functional ion channels and that the stably transfected HEK-293 cell line serves as a unique system for studying human alpha 7 nicotinic receptor function and regulation, and for examining ligand interactions. |
PubMedSearch : Gopalakrishnan_1995_Eur.J.Pharmacol_290_237 |
PubMedID: 7589218 |
Gopalakrishnan M, Buisson B, Touma E, Giordano T, Campbell JE, Hu IC, Donnelly-Roberts D, Arneric SP, Bertrand D, Sullivan JP (1995)
Stable expression and pharmacological properties of the human alpha 7 nicotinic acetylcholine receptor
European Journal of Pharmacology
290 :237
Gopalakrishnan M, Buisson B, Touma E, Giordano T, Campbell JE, Hu IC, Donnelly-Roberts D, Arneric SP, Bertrand D, Sullivan JP (1995)
European Journal of Pharmacology
290 :237