The phenolic monoterpenoid carvacrol inhibits the binding of nicotine to the housefly nicotinic acetylcholine receptor
Article first published online: 18 DEC 2012
© 2012 Society of Chemical Industry
Pest Management Science
Volume 69, Issue 7, pages 775–780, July 2013
How to Cite
Tong, F., Gross, A. D., Dolan, M. C. and Coats, J. R. (2013), The phenolic monoterpenoid carvacrol inhibits the binding of nicotine to the housefly nicotinic acetylcholine receptor. Pest. Manag. Sci., 69: 775–780. doi: 10.1002/ps.3443
- Issue published online: 12 JUN 2013
- Article first published online: 18 DEC 2012
- Accepted manuscript online: 19 OCT 2012 04:57AM EST
- Manuscript Accepted: 19 OCT 2012
- Manuscript Revised: 31 AUG 2012
- Manuscript Received: 11 APR 2012
The phenolic monoterpenoid carvacrol, which is found in many plant essential oils (thyme, oregano and Alaska yellow cedar), is highly active against pest arthropods, but its mechanisms of action are not fully understood. Here, carvacrol is shown to bind in a membrane preparation containing insect nicotinic acetylcholine receptors (nAChRs). [14C]-Nicotine binding assays with Musca domestica (housefly) nAChRs were used in this study to demonstrate carvacrol's binding to nAChRs, thereby acting as a modulator of the receptors.
Carvacrol showed a concentration-dependent inhibition of [14C]-nicotine binding in a membrane preparation of housefly heads containing nAChRs, with IC50 = 1.4 μM, in a non-competitive pattern. Binding studies with neonicotinoid insecticides revealed that imidacloprid and thiamethoxam did not inhibit the binding of [14C]-nicotine, while dinotefuran, from the guanidine subclass of neonicotinoids, inhibited nicotine binding like carvacrol.
Carvacrol binds to housefly nAChRs at a binding site distinct from nicotine and acetylcholine, and the nAChRs are a possible target of carvacrol for its insecticidal activity.© 2012 Society of Chemical Industry