Inhibitory Effects of Quercetin on Muscle-type of Nicotinic Acetylcholine Receptor-Mediated Ion Currents Expressed in Xenopus Oocytes.
10.4196/kjpp.2011.15.4.195
- Author:
Byung Hwan LEE
1
;
Tae Joon SHIN
;
Sung Hee HWANG
;
Sun Hye CHOI
;
Jiyeon KANG
;
Hyeon Joong KIM
;
Chan Woo PARK
;
Soo Han LEE
;
Seung Yeol NAH
Author Information
1. Department of Physiology, College of Veterinary Medicine and Bio/Molecular Informatics Center, Konkuk University, Seoul 143-701, Korea. synah@konkuk.ac.kr
- Publication Type:Original Article
- Keywords:
Flavonoids;
Quercetin;
Muscle-type nicotinic acetylcholine receptors;
Xenopus oocyte
- MeSH:
Acetylcholine;
Adult;
Flavonoids;
Fruit;
Ginkgo biloba;
Humans;
Inhibitory Concentration 50;
Ligand-Gated Ion Channels;
Lycopersicon esculentum;
Molecular Weight;
Neuromuscular Junction;
Onions;
Oocytes;
Quercetin;
Receptors, Nicotinic;
RNA, Complementary;
Vegetables;
Xenopus
- From:The Korean Journal of Physiology and Pharmacology
2011;15(4):195-201
- CountryRepublic of Korea
- Language:English
-
Abstract:
The flavonoid quercetin is a low molecular weight compound generally found in apple, gingko, tomato, onion and other red-colored fruits and vegetables. Like other flavonoids, quercetin has diverse pharmacological actions. However, relatively little is known about the influence of quercetin effects in the regulation of ligand-gated ion channels. Previously, we reported that quercetin regulates subsets of nicotinic acetylcholine receptors such as alpha3beta4, alpha7 and alpha9alpha10. Presently, we investigated the effects of quercetin on muscle-type of nicotinic acetylcholine receptor channel activity expressed in Xenopus oocytes after injection of cRNA encoding human fetal or adult muscle-type of nicotinic acetylcholine receptor subunits. Acetylcholine treatment elicited an inward peak current (IACh) in oocytes expressing both muscle-type of nicotinic acetylcholine receptors and co-treatment of quercetin with acetylcholine inhibited IACh. Pre-treatment of quercetin further inhibited IACh in oocytes expressing adult and fetal muscle-type nicotinic acetylcholine receptors. The inhibition of IACh by quercetin was reversible and concentration-dependent. The IC50 of quercetin was 18.9+/-1.2 microM in oocytes expressing adult muscle-type nicotinic acetylcholine receptor. The inhibition of IACh by quercetin was voltage-independent and non-competitive. These results indicate that quercetin might regulate human muscle-type nicotinic acetylcholine receptor channel activity and that quercetin-mediated regulation of muscle-type nicotinic acetylcholine receptor might be coupled to regulation of neuromuscular junction activity.
