Differential Regulations of Quercetin and Its Glycosides on Ligand-Gated Ion Channels

Access this Article

Author(s)

Abstract

Quercetin, one of the flavonoids, is a compound of low molecular weight found in various plants and shows a wide range of diverse neuropharmacological actions. In fruits and vegetables, quercetin exists as monomer- (quercetin-3-<i>O</i>-rhamnoside) (Rham1), dimer- (Rutin), or trimer-glycosides [quercetin-3-(2<sup>G</sup>-rhamnosylrutinoside)] (Rham2) at carbon-3. In the previous studies, we demonstrated that quercetin inhibits both glycine and 5-hydroxytryptamine type 3, (5-HT<sub>3A</sub>) receptor channel activities expressed in <i>Xenopus</i> oocytes. However, the effects of quercetin glycosides on glycine and 5-HT<sub>3A</sub> receptor channel activities are not well known. In the present study, we investigated the effects of quercetin glycosides on the human glycine α1 receptor and mouse 5-HT<sub>3A</sub> receptor channel activities expressed in <i>Xenopus</i> oocytes using a two-electrode voltage clamp technique. In oocytes expressing glycine or 5-HT<sub>3A</sub> receptors, quercetin- or its glycosides-induced inhibitions on glycine- (<i>I</i><sub>Gly</sub>) and 5-HT-induced current (<i>I</i><sub>5-HT</sub>) were dose-dependent and reversible. Applications of quercetin and its glycosides inhibited <i>I</i><sub>Gly</sub> in order of quercetin>Rutin≥Rham1>Rham2. Applications of quercetin and its glycosides inhibited <i>I</i><sub>5-HT</sub> in order of Rham2≥quercetin>Rutin=Rham1. The inhibitions of <i>I</i><sub>Gly</sub> by quercetin glycosides were non-competitive and voltage-sensitive, whereas the inhibitions of <i>I</i><sub>5-HT</sub> by quercetin glycosides were competitive and voltage-insensitive manners. These results also indicate that quercetin glycosides might regulate the human glycine α1 and mouse 5-HT<sub>3A</sub> receptors with differential manners.

Journal

  • Biological and Pharmaceutical Bulletin

    Biological and Pharmaceutical Bulletin 31(4), 611-617, 2008-04-01

    The Pharmaceutical Society of Japan

References:  29

Codes

  • NII Article ID (NAID)
    110006680495
  • NII NACSIS-CAT ID (NCID)
    AA10885497
  • Text Lang
    ENG
  • Article Type
    ART
  • ISSN
    09186158
  • NDL Article ID
    9431637
  • NDL Source Classification
    ZS51(科学技術--薬学)
  • NDL Call No.
    Z53-V41
  • Data Source
    CJP  NDL  NII-ELS  J-STAGE 
Page Top