Potentiation of human alpha4beta2 neuronal nicotinic receptors by a Flustra foliacea metabolite.
The effects of various Flustra foliacea metabolites on different types of human neuronal nicotinic acetylcholine receptors (nAChRs) expressed in Xenopus oocytes were investigated. Whereas most of the compounds tested had a small blocking effect, one of them, deformylflustrabromine, selectively increased the current obtained in alpha4beta2 receptors when co-applied with acetylcholine (ACh). The current increase was reversible and concentration-dependent. This potentiating effect was still present at saturating concentrations of acetylcholine, and no changes in single-channel conductance or reversal potential were observed, thus suggesting a modification in the gating of alpha4beta2 receptors. Dwell time analysis of single channel records indicates that the mechanism of action of deformylflustrabromine could be both an increase of the opening rate constant and a decrease of the closing rate constant on alpha4beta2 receptors. Thus, deformylflustrabromine may constitute an excellent starting point for the future development of related agents able to potentiate human neuronal nicotinic receptor function.
Sala
Francisco
F
Instituto de Neurociencias, Universidad Miguel Hernández-CSIC, Sant Joan d'Alacant, Apdo, Correos 18, 03550 Alicante, Spain.
Mulet
José
J
Reddy
Krishna P
KP
Bernal
José Antonio
JA
Wikman
Philip
P
Valor
Luis Miguel
LM
Peters
Lars
L
König
Gabriele M
GM
Criado
Manuel
M
Sala
Salvador
S
D000818:Animals; D002013:Bryozoa / Q000378:metabolism*; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D006801:Humans; D007211:Indoles / Q000494:pharmacology*; D015640:Ion Channel Gating / Q000187:drug effects / Q000502:physiology; D008564:Membrane Potentials / Q000187:drug effects* / Q000502:physiology; D009865:Oocytes / Q000378:metabolism; D018408:Patch-Clamp Techniques; D011978:Receptors, Nicotinic / Q000187:drug effects* / Q000378:metabolism; D014981:Xenopus
D007211:Indoles; D011978:Receptors, Nicotinic; C473008:deformylflustrabromine; C403531:nicotinic receptor alpha4beta2