Effects of grape seed proanthocyanidin on 5-hydroxytryptamine(3) receptors in NCB-20 neuroblastoma cells.
Biol Pharm Bull
; 34(7): 1109-15, 2011.
Article
em En
| MEDLINE
| ID: mdl-21720021
ABSTRACT
Proanthocyanidin is a phenolic compound present in plants, that has antioxidant, antinociceptive, anti-emetic, and neuroprotective properties. We investigated the actions of proanthocyanidin from grape seeds on 5-hydroxytryptamine (5-HT)(3) receptors in NCB-20 neuroblastoma cells using a whole-cell voltage clamp technique. Co-treatment of proanthocyanidin (0.3-100 µg/ml) and 3 µM 5-HT (near EC(50)) produced a slight inhibition of 5-HT-induced inward peak current (I(5-HT)) in NCB-20 cells, but pretreatment with proanthocyanidin for 30 s before application of 5-HT induced a much larger inhibition of I(5-HT) in an irreversible, concentration- and time-dependent manner (IC(50)=6.5±0.4 µg/ml, Hill coefficient=2.5±0.1). Proanthocyanidin also produced a concentration-dependent inhibition of currents induced by 30 µM 5-HT, near-maximal concentration (IC(50)=22.1±0.4 µg/ml, Hill coefficient=2.4±0.1). High concentrations (â§30 µg/ml) of proanthocyanidin caused a concentration-dependent inhibition of the activation and desensitization of currents induced by 30 µM 5-HT. Further studies showed that pretreatment of 20 µg/ml proanthocyanidin caused not only a rightward shift of the dose-response curve for 5-HT (EC(50) shift from 2.7±0.4 to 6.2±0.5 µM), but also a decreased E(max) (inhibition by 37.5±1.3%). The proanthocyanidin-induced inhibition of 5-HT(3) receptors did not show a significant difference within the testing holding potential ranges (-50-+30 mV). These results suggest that proanthocyanidin inhibits 5-HT(3) receptor function in NCB-20 cells in a noncompetitive mode, and that this inhibitory effect of proanthocyanidin probably contributes to the pharmacological actions of proanthocyanidin.
Buscar no Google
Base de dados:
MEDLINE
Assunto principal:
Sementes
/
Vitis
/
Proantocianidinas
/
Receptores 5-HT3 de Serotonina
Limite:
Humans
Idioma:
En
Revista:
Biol Pharm Bull
Assunto da revista:
BIOQUIMICA
/
FARMACOLOGIA
Ano de publicação:
2011
Tipo de documento:
Article